CLEVELAND (AP) -- Cavaliers rookie point guard Kyrie Irving remains day to day because of a concussion that sidelined him for one game and could keep him out a few more.
Irving was evaluated at the Cleveland Clinic on Thursday, one day after he was diagnosed with a concussion shortly before the Cavs beat the Los Angeles Clippers. Irving, who was accidentally kneed in the head during Tuesday's game in Miami, complained of a headache after warming up and missed his first game this season.
His backup, Ramon Sessions, scored 24 points with 13 assists in Cleveland's 99-92 win.
The team said in a release that Irving was seen by Dr. Rick Figler at the Center for Sport Health at Cleveland Clinic. The Cavs did not practice Thursday.
The team is treating Irving's head injury conservatively and cautiously, following the NBA's new guidelines on concussions. Because concussions differ from person to person, there's no way to predict when Irving will be cleared to resume basketball activities.
In December, the league put its concussion policy in place to determine when players can return from head injuries.
If a player is diagnosed with a concussion, he will have to complete a series of steps to confirm that he's healthy enough for competition. Once he is symptom free, the player must make it through increasing stages of exertion -- from a stationary bike, to jogging, to agility work, to non-contact team drills -- while ensuring the symptoms don't return after each one.
Then, the neurologist hired to lead the league's concussion program needs to be consulted before the player is cleared.
The process will likely take at least several days, if not weeks.
Cleveland hosts Milwaukee on Friday and Philadelphia on Saturday, and it's possible Irving could sit out both games. The Cavs play their next eight games at home.
Irving, who does not have a history of concussions, was driving to the basket in the fourth quarter Tuesday when he banged into Heat forward Chris Bosh. Irving fell backward and hit his head on Dwyane Wade's knee. He stayed in the game and made two free throws before he was taken out by coach Byron Scott with 1:27 left.
Irving spoke to reporters following the game and was in a playful mood, joking with teammate Luke Harangody.
The 19-year-old didn't mention his headache until later. The Cavs did not have a shootaround on Wednesday and Irving reported to Quicken Loans Arena in the afternoon and took part in a team walkthrough at 4:30 in the practice gym. It was later while taking some shots on the arena's main floor that he began feeling worse and told trainer Max Benton.
"He went out and warmed up and said his head felt like it was on fire," Scott said.
Irving was diagnosed with the concussion by Dr. AJ Cianflocco and stayed in the locker room during the game.
The No. 1 overall pick in this year's draft, Irving is averaging 18 points and 5.1 assists for the Cavs, who are a surprising 10-14 in Scott's second season. Irving was chosen to participate in the "Rising Stars" game during All-Star weekend this month in Orlando.