SANTA CLARA -- Cracking the 49ers' 53-man roster proved as difficult as anticipated.

That's what happens when most everyone returns from a storybook season, one that came within an overtime loss of the Super Bowl.

Most notably, third-string quarterback Scott Tolzien is among those coming back.

Tolzien survived one of the most scrutinized battles of training camp, outlasting Oakland native Josh Johnson to once again back up starter Alex Smith and Colin Kaepernick.

Johnson was among 22 players ousted Friday from the 49ers' roster. Of the 53 who made it, 42 were on last season's team, including 21 of 24 defenders.

Neither general manager Trent Baalke nor coach Jim Harbaugh was made available for comment. Harbaugh will hold a noon news conference Saturday.

While 21 players got released, one former draft pick was traded to the Carolina Panthers: second-year safety Colin Jones for a reported seventh-round draft pick. Jones, a 2011 sixth-round draft pick out of TCU, played mainly on special teams last season, and three of his 11 tackles came in the playoffs.

Running back Rock Cartwright, an 11th-year veteran, was Friday's first roster casualty to announce his fate on Twitter: "Wanna thank the 49ers for the opportunity." Cartwright was slated to fill the special-teams role left by Blake Costanzo, who signed with the Chicago Bears in free agency.

Cartwright's exit paved the way for Anthony Dixon to stick. Dixon's

One surprise survivor was undrafted tight end Garrett Celek, brother of Philadelphia Eagles tight end Brent Celek. A 3-yard touchdown catch in Thursday's exhibition finale might have cemented Garrett Celek's status.

Celek beat out 2011 practice-squad tight end Konrad Reuland, a Stanford product and one of seven players cut despite being coached in college by Harbaugh.

Other Harbaugh pupils cast aside were wide receiver Chris Owusu, safety Michael Thomas, defensive tackle Matthew Masifilo and tackle Derek Hall from Stanford; and University of San Diego products Johnson and Eric Bakhtiari, a journeyman linebacker.

Johnson spent his first four seasons with the Tampa Bay Buccaneers before signing a two-year contract in March. He pocketed a $350,000 signing bonus upon reuniting with Harbaugh.

Tolzien's 41.9 passer rating in the exhibition season was dwarfed by Johnson's mark of 115.3, based on 15 of 29 passing for 219 yards with Thursday's two touchdown passes.

After debuting nicely in the exhibition opener (10 of 13, 84 yards), Tolzien didn't fare well Thursday against the Chargers (3 of 8, 42 yards). He had an interception in both those games, the only two thrown by 49ers quarterbacks in 117 attempts.

Outside linebacker Cam Johnson (seventh-round pick) became the second member cut from this year's seven-man draft class, following Monday's release of sixth-round center Jason Slowey.

With six running backs and six wide receivers, the 49ers kept only eight offensive linemen, including backups Leonard Davis, Daniel Kilgore and fourth-round pick Joe Looney.

The search for backup safeties produced three: C.J. Spillman, Trenton Robinson and Darcel McBath, who intercepted Philip Rivers on Thursday. One name to consider on the waiver wire is Reggie Smith, the 49ers' third safety last season who was released by the Panthers.

Linebacker Michael Wilhoite, who drew praise from Harbaugh after Thursday's game, is expected to return on the eight-man practice squad, according to agent David Canter.

Friday's roster departures:

Offense (11): quarterback Josh Johnson; wide receivers Chris Owusu, Nathan Palmer, Brett Swain; tight ends Konrad Reuland, Kyle Nelson; running back Rock Cartwright; offensive linemen Al Netter, Derek Hall, Kenny Wiggins, Mike Person;

Defense (11): linebackers Eric Bakhtiari, Cam Johnson, Kenny Rowe, Michael Wilhoite, Joe Holland, Ikaika Alama-Francis; safeties Michael Thomas, Colin Jones (traded); defensive tackles Tony Jerod-Eddie, Matthew Masifilo; cornerback Anthony Mosley.