To be on top of (one's) game
Translation of "to be on top of (one's) game" into Russian
to be on top of (one's) game
быть на высоте, в отличной форме
After months of practice, the athlete is on top of his game.
После месяцев тренировок, спортсмен в отличной форме.
Definitions
To perform at the highest level of one's ability; to be functioning with maximum skill, efficiency, or effectiveness, often in a competitive or challenging situation.