Work Text:
Yelena has always considered herself a woman of science.
Not the boring kind, obviously - no lab coats, no clipboards, no guinea pigs involved (even more obviously because duh, she owns one) - but real science. The kind where you poke something dangerous with a stick just to see what happens. The kind that involves soldiers, unresolved feelings, and one very obvious metal-armed variable pretending very hard not to care.
Her hypothesis is simple: James Buchanan Barnes is down astronomically for Ava Starr. Embarrassingly, even.
The problem? Bucky himself either does not know this, or knows it but is actively lying to everyone, including himself and every type of god out there.
And Yelena?
Absolutely intends to fix that.
(Or at the very least, poke the issue with a proverbial stick, because that’s always fun.)
She decides on her plan of action on a Tuesday.
Which is important, because Tuesdays are for chaos. Wednesdays are for consequences, and Thursdays are for pretending none of it was ever done on purpose. Common knowledge and all that.
She’s perched on the edge of the gym mat with a water bottle she stole from John’s stash, watching Ava warm up. Ava rolls her shoulders and shakes out her hands, her expression loose and easy in that way she gets when what she’s involved in is just playful sparring, not a deadly mission or a kill zone of any kind.
Across the room, Bucky is - predictably - pretending very badly that he is not watching her. His face is neutral in the way that means he is definitely not: jaw tight, eyes flicking anywhere except directly at Ava. But Yelena has known him long enough to recognize the way his attention keeps snapping back to her like a magnet, anyway. He’s tracking her movement with soldier precision, all while acting like he’s religiously studying a crack in the concrete.
It’s pathetic, actually. The man really should be aware by now that talking to Ava is an option he could take.
Sadly, this is what happens to emotionally repressed idiots.
Makes for a fantastic source of entertainment, though.
Yelena grins into her bottle, delighted beyond belief.
Meanwhile, John stretches nearby, rolling his neck and clearly gearing up to be Ava’s sparring partner today. He looks annoyingly relaxed about it, too, smiling largely when Ava glances and subsequently tosses a rolling of the eyes at him.
And Bob, poor Bob, sits on a bench lacing and unlacing his gloves, watching everything with the vague anxiety of a man who knows something bad is coming but isn’t aware of the specifics. He’s also wearing boxing headgear - unnecessary because he’s basically bulletproof, by the way - which makes his adorable face look pinched. But that expression could also be because he just knows Yelena is absolutely up to no good this blessed Tuesday morning.
And, well, he is right.
She taps his nose, grins at him, then begins doing God’s work.
Yelena sidles up to John and steers him toward the water cooler with a grip that suggests any form of resistance will result in all kinds of bodily harm.
“Johnny, sweet Johnny,” she starts cheerfully, “you are about to help me ruin a good man’s day, just so you know.”
John squints at her, already suspicious - but deeply interested. “Ruin how? And whose?”
Bob trails behind them, already distressed. “I would like it on record that I do not support this.”
Yelena waves him off. “You’re already my accomplice. Your silence is support enough.”
Bob shuts up.
“Now, all I’m asking is very small favor,” Yelena tells John. She leans in closer. “You are already very annoying, but today I want you to be… how do you say… extra. In the mat. With Ava.”
He frowns. “How extra?”
“Very extra. Obnoxiously extra. So, you on a Friday night, essentially.”
“And why the hell should I do that for you?”
Yelena grins and tilts her head, eyes flicking pointedly toward Bucky, who has very obviously stopped pretending not to watch Ava unroll her shoulders with deep intensity.
John follows her gaze. Understanding dawns. Slowly. Dangerously.
“You want to mess with Barnes?”
Sometimes, she really appreciates how intelligent John can be.
“Yes,” Yelena agrees readily. “For science.”
“Oh,” he says. “Oh, you’re evil.”
She waves that off. “Hush. We all know this already. But, focus, John. When you spar with Ava later, I want you to be little bit… handsy.”
He chokes. “What?”
“Relax,” she says, patting his shoulder. “Not in a disgusting or creepy way, or I will kick your throat. Just–” She gestures vaguely. “Friendly. Flirty. Touch her waist when you pass. Steady her when she stumbles. Laugh. Maybe spin her little bit. You know. Be the absolute worst out there. But not enough to make her uncomfortable, or again, I will kick you in the throat.”
Bob’s head snaps up. “Excuse me, spin her? While sparring?”
Yelena beams at him. “You will learn many things about boxing sport today, Bob. I assure you, it's not all about punching and more punching.”
“That’s… wow.” John rubs a hand over his face. “Bucky’ll murder me for this, you know.”
“Yes,” Yelena tells him gravely. “But that is risk I am willing to take.”
John stares at her, and to his credit, doesn’t seem to be put off by the plan.
She pats his chest. “Plus, if he punches you, you get to punch him back, so. Violence is fun. And freeing.”
John exhales slowly. Then grins. “You know what? Fine, what the hell. For science.”
Yelena claps once. “Excellent. I knew you had sense. And do not worry; I will absolutely tell your son how good a man you are after you die. I take care of it. I might even avenge you. Probably. If I'm not too busy.”
“Wow. Thanks.”
Bob sighs. “I’m going to regret witnessing this, aren’t I.”
Yelena taps his cute nose again. “You will regret many things in your life, Robert. But not this. Never this.”
Sparring starts normally enough.
Ava and John circle each other, light on their feet, oozing confidence and capability that they regularly display on the field. She throws the first jab; he blocks, counters, retreats. It’s clean, controlled - very familiar. Soon, the training room settles into the rhythm of bodies moving, shoes squeaking, and breaths huffing.
Bucky’s rigid posture eases a fraction when he sees just how boring and normal things are.
Yelena clicks her tongue quietly. You haven’t seen anything yet, Buck.
Then John, smart man that he is, changes things.
On Ava’s next lunge, he doesn’t just sidestep; he catches her by the forearm and guides her past him, glove lingering at her waist a second longer than strictly necessary.
Ava blinks, surprised, but laughs it off anyway. “Hey–”
“Sorry,” John says easily, grin wide. “Momentum. You know how it goes.”
Yelena watches Bucky’s shoulders go rigid.
Oh. Yes.
She nudges Bob beside her and stage-whispers: “Observe. Our winter popsicle is starting to defrost nicely.”
He sighs. Deeply. “Lena–”
“Shh!”
Ava recovers quickly, sweeping his legs in one smooth action. John stumbles back, and when she straightens, he reaches out automatically to steady her, gloves briefly resting at her hips.
“Careful,” he says.
She swats his touch away with her gloves. “You’re the one who needs to be careful, Walker.”
He raises both hands in a universal gesture of surrender. “Hey. Just looking out for you here.”
“Don’t bloody need it.”
John laughs. “Yeah, you don’t. That’s what I like about you, you know.”
Bucky’s eyes narrow.
Ava rolls her eyes at John again. “Are we actually sparring, or would you really rather just yap the morning away?” She steps closer and swats his shoulder. “What’s the matter? Getting slow in your old age?”
“You only wish you could be as slow as me.”
She laughs. “Never.”
Bob glances at Bucky and makes a strangled noise at the back of his throat.
Yelena bites her lip to keep from cackling.
John and Ava have always had this easy camaraderie between them, anyway. The kind that, if exploited, can easily make Bucky unravel.
And, sure enough? The metal man is dying. Subtle, but the signs of deceasement are there.
Bucky uncrosses his arms.
He recrosses them.
Then uncrosses them again.
His jaw flexes. He takes a step forward, then stops himself, visibly schooling his expression back into something neutral that fools no one.
Ava doesn’t notice, of course. She’s too busy sparring with John - physically and verbally - and too used to casual contact in the mat to read anything into it.
John, however, is absolutely, purposely reading into it.
On the next exchange, Ava ducks under his arm, and John, very smoothly, spins her out of it, one hand at her back, guiding her into position before releasing her.
“Show off,” she says, smiling despite herself.
“You know you love it,” he replies.
Bucky’s metal hand clenches. His foot taps - once, twice.
Bob whispers, “Oh my god.”
Yelena whispers back, “Is very beautiful, yes? Like art.”
He squints at her. “Art of killing Bucky slowly, you mean?”
She beams at him. “You are learning, Sweet Bob. I’m very proud.”
He sighs.
Things escalate, but gently. John laughs more. He bumps Ava’s shoulder with his own when she lands a hit. He gives her tips about “lowering her center of gravity” or some shit. And when she trips during a feint, he catches her instinctively, grip firm and comforting, murmuring, “Hey. Steady now. Wouldn’t want you hurting yourself.”
From the outside, it’s all harmless. Supportive teammate stuff. Normal training material.
From Bucky’s perspective, however, Yelena imagines this to be a very slow, grinding test of restraint.
She watches him with professional appreciation. The way his weight shifts forward, like he’s bracing to step in. The way his eyes track John’s hands with surgical precision. The way his mouth tightens every time Ava laughs, beautiful and carefree.
Bob leans over. “Should we stop this? I think we should–”
“No,” Yelena cuts in. “We haven’t reached best part yet.”
Ava sweeps John’s legs again. He gets floored with an oof, and when she follows down to casually rest one knee on his chest, his hand lands - accidentally, maybe - over her hips again.
John taps out, grinning all the while. “Damn, Ghost Lady. You’re vicious today.”
“Only to losers,” Ava tells him, matching his grin. “Like you.”
Yelena whistles and claps. “Knee him in the groin!” she calls out, making John groan and Bob gasp.
Ava looks back at her and laughs. “Should I?” She turns her attention back to John. “Maybe I–”
And that’s when Bucky moves.
He strides onto the mat - cool, calm, collected - but the lines around his mouth say he’s anything but.
“That’s enough,” Bucky says sharply.
Ava, still sitting just below John’s sternum, glances at him, smile dying down on her face when he sees just how stern Bucky appears to be. “What?”
“Time for a switch,” Bucky replies, already pulling his gloves on. “Walker. You’re with me.”
Even on the floor, John’s smile is feral. “Sure thing, Buck. Whatever you say.” Then, because he’s insane, he taps Ava’s hips again and tells her, “Hey, you heard the old man. Get off me.”
Ava opens her mouth, looks at Bucky again, then shrugs. “Fine. Guess it’s time for a break, anyway.”
Bucky holds his hand to her to help her up. Ava glances at it, slaps his wrist away, then gets to her feet on her own before hopping off the mat, completely unconcerned.
He watches her go without a word.
Bob watches Ava go, too, then looks at the mat again like he’s about to witness a car crash.
Yelena smiles at him. “Now this is best part. Watch and learn.”
Bucky and John square off.
There is no warm-up banter. No friendly smiles or jokes. Just pure super-serumed testosterone - a masterclass in controlled aggression.
The first exchange - as expected - is brutal.
Bucky comes in hard and fast, forcing John back with a flurry of controlled but unmistakably aggressive strikes. John blocks and grunts, forced to adjust his stance more than once in the face of Bucky’s… Buckiness.
“Something on your mind there, bud?” John asks between blows, now wearing a shit-eating grin.
Bucky says nothing.
Like Ava, he focuses on sweeping John’s legs from under him. John barely recovers; Bucky had both strength and weight behind his movements, after all. They grapple, break, then circle again. Bucky moves like a storm held in check. Every strike is precise. Every block surgical. And really, John fights well, but here, he’s reacting, not leading. Definitely not a good thing while sparring.
Yelena watches, delighted. “I think Bucky did not like the spinning. Or the straddling. Or the everything.”
“No kidding,” Bob mutters, eyes on the two men. "Remind me never to touch Ava while Bucky's present?"
"Not that you should, but okay."
John ducks a hard punch and finds time to comment, “You’re so tense, Barnes. Jesus. Maybe you should–”
Bucky slams him to the mat. Hard.
Not enough to hurt him, obviously. But enough to shut him up and make a point.
They separate again, breathing hard.
From the sidelines, a somewhat alarmed Ava calls, “Hey! You two good?”
“Fine!” Bucky snaps.
“Great!” John says at the same time. “Not at all dying here or anything!”
Ava frowns at them. Then she walks over to Yelena and nudges her arm. “What’s up with Bucky? He’s acting all weird.”
“Is he?” Yelena replies, the picture of perfect innocence. “I haven’t noticed.” Then she turns away and presses a fist to her mouth to keep from laughing out loud.
The spar ends a few minutes later with both men sweaty, bruised, and very clearly worked out. They disengage without a word.
Ava returns to the mat, handing Bucky a towel before throwing another that lands perfectly on John’s head. “You went hard on John there, Buck. You okay?”
He takes the towel, muttering, “Yeah, guess I overdid it. Sorry.”
She shrugs. “Guess you needed the exercise.”
And that’s it. No accusation. No realization of why Bucky very purposely overdid things to John.
Just Ava being… well, Ava.
Meanwhile, John catches Yelena’s eye across the room. “You fucking owe me for this,” he mouths at her.
“We talk payment later,” she mouths back. But he barely notices, since Ava’s made her way to him at that point, presumably to check if he’s still breathing and in one piece.
Bob sinks back on the bench, rubbing his face. “Wow. I can’t believe I witnessed all of that.”
Yelena slings an arm around his shoulders. “The beauty of team sparring. You’re very welcome, by the way. Also, prepare yourself, Bob: we’re the ones scheduled on the mat next. And I may or may not spin or straddle you, so.”
Bob gulps.
Yelena grins.
And then she spots Bucky quietly toweling himself off to the side.
Time to escalate things. Again.
She sidles up to Bucky and says, loudly, “Good exercise, no? Very… invigorating. For you.”
Bucky purposely doesn’t look at her when she speaks. He doesn’t look at Ava and John’s general direction, either. He just drags the towel over his neck, jaw tight enough to crack teeth. “It was… fine,” he says flatly.
Yelena hums, circling him like a curious cat. “Mm. Yes. You always hit your teammates like that when you’re fine.”
He shoots her a warning look. “Don’t.”
She smiles brightly. “Don’t what? Observe patterns? Make mental note of how quickly you turned very murderous today towards a certain American Captain? Some might even think you’re–”
“Drop it, Yelena.”
And, because Yelena does value her life - somewhat - she actually does.
“All right, fine. Consider things dropped.”
And then she begins to walk away.
Only to say over her shoulder, “Jealousy is very bad for the joints, just so you know. You might want to work on that ASAP.”
Oh, and she can definitely feel his glare heating up her back now.
Delicious.
As Bucky stalks off toward the lockers, still scowling and day definitely ruined, Yelena watches him go with deep satisfaction.
Tuesday very well spent, then.