San Francisco 49ers coach Kyle Shanahan doesn't like to lose, especially when it's Jon Gruden on the opposite sideline.

The two coaches' relationship goes back to 2004, when Shanahan was an offensive assistant for the Tampa Bay Buccaneers under Gruden following a championship season.

During Thursday's Senior Bowl, the Oakland Raiders coach met his former assistant Shanahan for the first time as head-coaching rivals.

Shanahan, 38, also studied traits with other members of that legendary coaching staff, which included defensive coordinator Monte Kiffin, Pittsburgh Steelers head coach Mike Tomlin, Washington Redskins head coach Jay Gruden, Cowboys defensive coordinator Rod Marinelli, and Falcons assistant Raheem Morris, the Buccaneers head coach from 2009-2011.

“Tampa was as good of a place as I could ever go,” Shanahan told Eric Branch of the San Francisco Chronicle back in late October. He also noted that Gruden, then in his early 40s, was also ahead of the curve when it came to using computers.

“He was one of the first guys doing that stuff, probably being a little bit younger than most guys at that time,” Shanahan told Branch. “And he just introduced me to pretty much every play known to man.”

Gruden, 55, spoke on his former confidant, and what they called their notorious coaches room.

“Yeah, we had a lot of fun back in those days,” Gruden said. “The woodshed, I called it. People are going to take me to the woodshed here pretty soon if we don’t get this thing going.”

Jon Gruden finished with a 4-12 record in his 2018-19 comeback season in Oakland, while Kyle Shanahan also went 4-12 with the 49ers.

Hopefully the coaches can turn it around next year.