Charles Barkley is said to be practicing golf “five hours a day” to prep for a charity tournament with Phil Mickelson, Steph Curry and Peyton Manning on Friday.

Barkley has big shoes to fill: He’s stepping in for Tiger Woods to play in “The Match: Champions for Change” game. The others have already been trolling Barkley’s legendarily ugly golf swing on social media. But an insider told us that the competition is very real.

“These guys want to kill each other. The lobbying that’s going on right now — the egos — they care so much about winning. If you put four of the most competitive people out there, they don’t want to be embarrassed. Chuck has been practicing five hours a day. Steph is a phenomenal golfer. He’s been practicing like crazy.”

Curry helped re-establish golf teams at Howard University, and this year’s event, broadcast on TNT, will benefit historically black colleges and universities.