Donating Prize Money for Haitian Relief ...

Tennis star Naomi Osaka has stepped up in a big way to help victims of the massive earthquake in Haiti ... she's opening her wallet to provide badly-needed assistance.

Naomi has pledged to donate whatever prize money she wins at nest week's Western & Southern Open to the Haitian relief effort.

Naomi, whose dad is Haitian, said, "Really hurts to see all the devastation that's going on in Haiti, and I feel like we really can't catch a break," adding, "I'm about to play a tournament this week and I'll give all the prize money to relief efforts for Haiti. I know our ancestor's blood is strong we'll keep rising."

The massive, 7.2-magnitude quake rocked Haiti Saturday. The casualty numbers are not…