Source: Alex Smith clears tests

San Francisco 49ers quarterback Alex Smith has been cleared medically after concussion testing, but the team is proceeding with plans to start Colin Kaepernick on Sunday against the New Orleans Saints, according to a team source.

Niners coach Jim Harbaugh didn't name a starter Friday.

Smith told ESPN on Wednesday night that Harbaugh informed the two quarterbacks that Kaepernick would take all the first-team reps in practice this week leading into Sunday's game.

Smith practiced Thursday and Friday in a non-contact jersey. Offensive coordinator Greg Roman told 49ers.com that the QB had not been cleared to play but hoped Smith would be cleared Friday.

"He's looked good, really sharp," Roman said. "He's gotten plenty of practice time. There's a lot of different scenarios this week and it's fluid. We talk through them, and it will change according to how the big picture changes, and obviously the quarterback position is a huge piece of that."

Harbaugh said Wednesday the QB for the NFC West-leading Niners (7-2-1) could change week to week, and even during the course of a game.

Smith missed Monday night's 32-7 rout of the Bears while recovering from a concussion. He was supportive Wednesday of the success of Kaepernick, who led the team against Chicago.

"If you can't be happy for your teammate's success you're playing the wrong sport. Go play tennis or golf or something," Smith said. "That's ridiculous, I think. That doesn't belong in team sports, in my opinion. It's the quarterback position. It gets a lot of attention. We're going to get talked about."

Smith completed 18-of-19 passes for 232 yards and three touchdowns without an interception in a Monday night win Oct. 29 at Arizona for a passer rating of 157.1. Smith then sustained a concussion in the second quarter of a 24-24 tie against St. Louis on Nov. 11. He even threw a touchdown pass with blurred vision six plays after taking the hit doctors believe caused his injury.

Kaepernick went 16 of 23 for 243 yards, two touchdowns and an impressive passer rating of 133.1 in his first NFL start Monday night against Chicago. The second-round draft pick out of Nevada in 2011 hardly seemed fazed by football's big stage.

Harbaugh rated Kaepernick's debut start as "A-plus-plus."

Information from ESPN's Trent Dilfer and John Clayton and The Associated Press was used in this report.