SWISS tennis ace Stan Wawrinka made one lucky ball boy’s day when he invited the teenager to help him warm up during a break.

While Victor Troicki was getting some attention from medical staff, Wawrinka brought the ball boy on court and lent him a racquet so the two could have a hit.

The Roland Garros crowd were amused by the gesture, as the ball boy held his own against the world no. 4.

When Troicki returned following treatment on his right leg, Wawrinka and the ball boy were given a hearty applause.

The defending French Open champion went on to win the match 7-6 (5), 6-7 (7), 6-3, 6-2.

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