The San Francisco 49ers' 24-13 loss to the Oakland Raiders Sunday has to be considered somewhat ironic, given how much speculation there is that San Fran will trade Harbaugh to the Raiders in the off-season. Even if Harbaugh doesn't end up in Oakland, it's becoming more and more likely that he won't remain with the 49ers next year.

As such, Eric Mangini's name has been floating around as a possible replacement in San Fran.

ESPN's Mike Sando weighed in on the situation.

"When the 49ers added Eric Mangini as an offensive assistant before the 2013 season, I wondered whether they were grooming him as a Harbaugh successor," Sando wrote. "There is some thought Mangini took the Cleveland job too quickly after the Jets fired him, but he has now worked in multiple capacities over nearly four full seasons. Mangini has now coached on both sides of the ball. He has coached under two of the NFL's most successful coaches in Bill Belichick and Harbaugh. He and other former Belichick assistants have been criticized for trying to be like Belichick instead of just being themselves. Enough time has passed for Mangini to reinvent himself. On a side note, Mangini and general manager Trent Baalke were together with the New York Jets under Bill Parcells in the late 1990s."

Mangini went 23-25 as head coach of the New York Jets. He took over in 2006 at the age of 35, and had two winning seasons in his three years then. He then went 5-11 in both of his seasons with the Cleveland Browns (but, in his defense, who has had success with the Cleveland Browns?)

Mangini is currently working as the tight ends coach for the 49ers after a lengthy career on the defensive side of the ball.

Current SF defensive line coach, Jim Tomsula, is also rumored to be in contention for the position.

"The veteran Tomsula is one of the highest-paid position coaches in the NFL, according to league sources, and the 49ers have revised his contract on multiple occasions," ESPN's Adam Caplan wrote.

"Tomsula, who interviewed for the Vikings' head coaching vacancy after last season, also drew interest from another team, a league source said. And he would likely be on the top of the 49ers' list should Harbaugh leaver after this season."