Serious sparring, they usually managed to school their features, to keep things focused and on point. Like this? There was no need. Natasha could read his movements as much as his expressions, they were practically seamless when they were attempting to communicate with each other after all. There was no reason to really hide anything in this instance.
The light smile on his face probably wasn't the most professional of things, but at that point, it really didn't matter.
The quick pace of the moves meant that a light sweat was on the cards, and if they kept it up, getting to five pins would at least be a challenge for Nat. "I've missed these work out pants," she was close enough that he could still drop a hand to her butt, giving it a quick slap before her attack had him dodging backwards, even as he had to counter her leg swipe.