Former Auburn RB Brandon Jacobs saw sustained success during his seven-year stint with the New York Giants, who drafted him in the fourth round back in 2005, but his career fell flat when he signed with the San Francisco 49ers before the 2012 season.

Part of the reason for that, according to Jacobs, was that head coach Jim Harbaugh did not use the veteran back effectively, as he netted only seven yards on five carries throughout the season.

According to Jacobs, Harbaugh’s football shortcomings weren’t limited to RB management, as he told Tiki and Tierney on CBS Sports Radio that Harbaugh was in over his head when it came to the X’s and O’s of the game.

“Going somewhere where they don’t have route conversions into certain coverages was just absurd. They’re just running routes in the defense, getting people killed. Size and strength is what they had, and that’s why they won. Let’s be real. They had great assistant coaches, but Jim didn’t know what he was doing. Jim had no idea. Jim is throwing slants into Cover-2 safeties, getting people hurt. That guy knew nothing, man.”

At first, Jacobs said that Harbaugh seemed smart, but the cracks began to appear as he got to know the former 49ers coach better.

“Jim, I had a lot of respect for Jim when I was there – before I got to know him. I enjoyed my time there, but we didn’t see eye-to-eye. I knew a little bit more about football than what they led on.”

To his credit, Jacobs’ NFL career lasted longer than Harbaugh’s did as a head coach. He gained 4,849 yards and 73 touchdowns during his first seven years in New York, as well as winning two Super Bowls in 2007 and 2011 with the G-Men.