The 2014 season was not fun for 49ers head coach Kyle Shanahan.

Back then, he was the offensive coordinator for the Cleveland Browns, coaching under then-head coach Mike Pettine.

Shanahan spent just one season in Cleveland, resigning from the organization after reportedly disagreeing with the front office’s insistence on starting rookie quarterback Johnny Manziel.

This footage from Shanahan’s time with the Browns seems to back up the reports that he didn’t exactly vibe with Pettine and the culture within the organization.

I hope Kyle Shanahan used this moment as motivation to hang up 40 on Mike Pettine tonight 😂 pic.twitter.com/L2TbKM5DLu — Adam Lefkoe (@AdamLefkoe) October 16, 2018

Just one season into a three-year contract, Shanahan walked into Pettine's office and presented a laundry list of reasons for choosing to resign.

"It wasn't a PowerPoint presentation,'' he said in 2017 to reporters at Super Bowl LI (h/t cleveland.com). "It was all on paper. I gave a number of points -- 32 of them, which you guys were accurate on. I gave them to the head coach."

Pettine, a defensive-minded coach, lasted just one more season in Cleveland before being fired after a 3-13 season. After working with the Seattle Seahawks as a consultant, the Green Bay Packers hired Pettine to be the team’s defensive coordinator in 2018.

Shanahan now will go head-to-head once again with his former boss when the 49ers host Green Bay in the NFC Championship Game on Sunday.

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It worked out pretty well for Shanahan the first time around, as San Francisco crushed the Packers 37-8 at Levi’s Stadium in late November.

We’ll find out Sunday if Pettine can flip the script and exact some revenge of his own on Shanahan and the 49ers.

Programming note: NBC Sports Bay Area feeds your hunger for 49ers playoff coverage with special editions of “49ers Central” all week (8 p.m. Monday, Wednesday and Friday; 6 p.m. Tuesday and Thursday)

Also tune in at 2:30 p.m. Sunday for “49ers Pregame Live,” with Laura Britt, Jeff Garcia, Donte Whitner, Ian Williams and Grant Liffmann previewing the NFC Championship Game against the Packers. That same crew will have all the postgame reaction on “49ers Postgame Live,” starting at approximately 5:30 p.m.

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