Reilly Opelka is one of the biggest servers in tennis, and now he’s set to put his skills to use for the greater good at the Miami Open.

According to ATP Tour stats, the 6’ 11” (2.11 m) American can easily hit double-digit aces in a match, and he averaged more than 17 per match over the last year. He’ll hope to keep those numbers high in Miami, where every ace will help raise money for charity through his “Aces Give Flight” campaign.

“I’m going to be donating $100 for every ace I hit during the Miami Open. I will be donating to Wings For Life, which is a spinal cord research non-profit charity,” Opelka said in a video posted to social media.

“I’m going to be calling on my friends Cameron Norrie and Stefanos Tsitsipas to be doing the same.”

American player Tommy Paul also added his name to the cause, as he made a hilarious Step Brothers-style cameo in Opelka’s video to join Tsitsipas and Norrie in the ace challenge.

All donations will benefit Wings For Life, whose mission is to find a cure for spinal cord injuries. According to their website, they “fund cutting-edge scientific research and clinical trials in the USA and around the globe.”