A viral DIY tennis ball grunts every time it is hit, turning a quiet rally into comedy.

Oh the ball goes UH the ball goes UH Every hit,

it grunts back, the ball goes UH!

Now the players look nervous,

their grunts got beat,By a fuzzy yellow rival with no feet,They hit

it harder, it hollers more,Standing ovation from the baseline floor!Smash it overhead

— UH!Drop it soft — UH!Every hit,

it grunts back, louder than before,The ball grunts back — UH!

The ball grunts back...