Not because she hasn't played for a long time.
It's because they're in a group fight. Individual strengths and weaknesses start to cancel out, while strategy becomes important. Her playing style may also serve an advantage in a group fight as she can finish off people who are low on hp. However, her play style is very very simplistic. For simplistic skills, it's just as easy to lose them as you can gain them; in this case, Uchicha can get her skill highest skill level back within no more than 2 hours (on a scale of combat complexity she probably ranks no higher than 2). For complex skills, like poosting, switch tactics, using 3rd person, etc, the time it takes to get these skills is much longer that the time it takes to lost them (on a scale of combat complexity, I would rank 8 or higher). Muscle memory also helps re-attain simple skills, such as Uchicha's here.