dr. james betz watched the injury on tv. he's a trauma surgeon at oakland's children's hospital. every concussion is unique and so is recovery. >> it may take hours or weeks or days. but that's where sequential re-examination by experts and believe me all of these professional teams have experts, will then determine whether or not someone is ready. >> what? >> so day to day. >> reporter: news of the concussion reached the fan store at oracle. >> if's a big blow but we've got a week left. so hopefully, he'll be back. he can't have the splash brothers with just one brother. >> would like to have thompson in. but i don't think that's going to stop us from winning. >> reporter: fans are sending this message to klay. >> hurry back, we need you. >> reporter: abc 7 news. >>> the policy requires a player to pass a series of tests. if the player experiences any concussion symptoms along the way, they have to go back to the previous stage and start over. the protocol also requires the team physician to discuss the process with the director of the nba's concussion program before clearing a

dr. james betz watched the injury on tv. he's a trauma surgeon at oakland's children's hospital.que and so is recovery. >> it may take hours or weeks or days. but that's where sequential re-examination by experts and believe me all of these professional teams have experts, will then determine whether or not someone is ready. >> what? >> so day to day. >> reporter: news of the concussion reached the fan store at oracle. >> if's a big blow but we've got a week left. so hopefully, he'll be back. he can't have the splash brothers with just one brother. >> would like