SANTA CLARA, Calif. (AP) Adrian Peterson's absence for all but one game last season left a huge hole for Minnesota on offense. NaVorro Bowman being sidelined the entire year was a similar blow for San Francisco's staunch defense.

Stars on opposite sides of the ball will likely meet up quite a few times Monday night as they make their highly anticipated returns - Peterson following paid leave and then a suspension last year in the fallout from a child-abuse case against him in Texas; Bowman back from a frightening left knee injury in the NFC championship game at Seattle in January 2014 that required surgery.

Peterson sat through a longer preseason of five games, so the season opener against the 49ers at Levi's Stadium couldn't come soon enough for the running back.

''It's been long, man, especially with the additional game and just pretty much going through the motions of just practice and the games and not playing,'' he said. ''Just kind of anticipating that first game Monday night. But it's almost here now. So that's a good feeling, you know? The mind is getting ready. The body is ready. So just looking forward to that Monday night.''

Bowman made a snazzy spin move in his first practice of training camp, then had three tackles on three snaps in his first preseason game.

The three-time All-Pro linebacker has spoken to Peterson on occasion about their similar comebacks from knee surgery.

''He went through the same thing,'' Bowman said. ''We just talked about the injury, really what he did, the specifics, to get back to where he is today. Off the field, we're co-workers, we're friends, we try to just talk about the game. We're competing against each other.''

Monday marks Jim Tomsula's debut as head coach for the 49ers after being promoted from his defensive line duties to replace Jim Harbaugh, now at Michigan. Tomsula served as interim coach for the final game in 2010 after Mike Singletary's firing.

Here are some things to watch for in the teams' season opener under the lights:

DEFENDING PETERSON: San Francisco's once-fearsome front seven has changed drastically in a matter of months.

Five-time All-Pro Patrick Willis walked away in March at age 30, then his heir apparent, Chris Borland, also called it quits following a sensational rookie season. Veteran defensive end Justin Smith was next to retire.

Peterson has never scored a touchdown against the Niners in three subpar performances, and now might be his best chance in a while.

The 30-year-old could regain his running swagger in a hurry against this new-look group, which will welcome the return of Bowman.

''He's a great player, to go in there, and have time off and do the things that he did coming back from an injury,'' second-year Minnesota coach Mike Zimmer said of Bowman. ''We're kind of hoping Adrian does the same thing when he comes back.''

In three meetings, Peterson has a combined 58 carries for 174 yards while facing San Francisco as a rookie in 2007 at Candlestick Park; 2009 in his third year at Minnesota; and in Year 6 in 2012 coming off his recovery from ACL surgery, again at Minnesota, where he had 25 rushes for 86 yards.

TOMSULA'S INTERVIEW: Tomsula interviewed with the Vikings last year when they hired Zimmer.

''First of all it was extremely humbling,'' he said. ''Obviously, just a wonderful experience. Very grateful.''

HAYNE'S DEBUT?: Jarryd Hayne just wants to play, in any role, now that he defied expectations to make the 49ers' 53-man roster as a capable return man.

Tomsula hasn't said what role rookie former Australian rugby league star Hayne will have, or even whether he will be among the 46 players who dress on game day.

In fact, special teams coach Thomas McGaughey Jr. hinted Hayne might not be returning punts.

''Everybody is flying the Hayne Plane right now, but if you look at who led our team in punt returns in the preseason, it wasn't Jarryd Hayne,'' McGaughey said. ''It was DeAndrew White.''

THE SOD FACTOR: After training camp kicked off with yet further problems at Levi's Stadium as the sod came loose, the two home exhibition games were no problem. A full new field was installed for Monday following a partial re-sodding after an Aug. 29 concert by Luke Bryan that took the Niners through their last exhibition game Sept. 4 against San Diego.

BLACK UNIFORMS: The 49ers will debut their black alternate jerseys for the first of two games they plan to wear them this season. San Francisco also will don the black uniforms in a Week 12 matchup against NFC West rival Arizona Cardinals on Nov. 29 at Levi's Stadium.


AP Pro Football Writer Dave Campbell in Minneapolis contributed to this report.


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