A look at potential 49ers coordinators under Jim Tomsula

The cynical view from the moment word began to leak well before the season opener that Jim Harbaugh’s coaching career with the San Francisco 49ers was on its deathbed was that Jim Tomsula was the clubhouse leader to replace him.

The pragmatic view was this: Tomsula’s candidacy depended upon his not only having to look for a new defensive coordinator since Vic Fangio would surely depart upon being passed over by a position coach but also Tomsula finding a strong offensive coordinator to right what went wrong with quarterback Colin Kaepernick & Co. this past season.

Perhaps more strange than Tomsula's elevation was the fact it was never revealed that he had a formal interview, in which Tomsula would assuredly be asked his plans for naming coordinators.

So who potentially fits, if Fangio is indeed gone, along with Greg Roman, who left to become Rex Ryan’s offensive coordinator with the Buffalo Bills?

Jason Tarver, the Oakland Raiders' former defensive coordinator whose contract expired this week, is a candidate for the same position with the 49ers, an NFL source confirmed.

Tarver coached with the Niners from 2001 to 2010 as an offensive quality control coach, assistant running backs/offensive assistant and outside linebackers coach. He served with Tomsula for four years and coached a young Patrick Willis before heading to Stanford for a year and then becoming the Raiders' defensive coordinator in 2012.

With degrees in chemistry, biochemistry and molecular biology, the Phi Beta Kappa member was known as a "mad scientist" and "baby genius" for his radical schemes in Oakland.

His Raiders defenses ranked 18th, 11th and 12th overall. Tarver, though, ran a 4-3 base defense in Oakland, and the 49ers have run a 3-4.

Current 49ers secondary coach Ed Donatell could also be a candidate, to at least keep the continuity theme going, as well as linebackers coach Jim Leavitt.

Offensively, Tomsula has been linked to former Chicago Bears coach Marc Trestman, who was fired after going 13-19 in two seasons.

Trestman is known for a high-powered passing attack, at least when it works. With the Bears, the philosophy did not. Not with Jay Cutler at quarterback, though the Bears did beat the 49ers in Week 2, the regular-season debut of Levi's Stadium in Santa Clara, California.

Before joining the Bears, Trestman was a head coach in the CFL with the Montreal Allouettes. Before that, he had last been in the NFL in 2004 and was the Raiders' offensive coordinator the last time they went to the playoffs, in the 2002 season, and was the Niners' offensive coordinator in 1995 and 1996 under George Seifert.

But if Trestman brings a wide-open offensive attack rather than a ground-and-pound, power running game, that would seem to be counterproductive to the 49ers' current personnel, as witnessed last season while the Niners limped to an 8-8 record.

Former Cleveland Browns offensive coordinator Kyle Shanahan has been linked to the opening in recent weeks, and the Niners interviewed Denver Broncos playcaller Adam Gase for the head-coaching gig. While both have a good reputation for developing quarterbacks, they also have wide-open philosophies. An out-of-box name to keep in mind, then, would be 49ers QBs coach Geep Chryst, who is already intimately familiar with Kaepernick.

Tomsula will be introduced to the media Thursday and is sure to be asked about his philosophies and potential candidates.