With the NFL's coaching shuffle in full swing after a rash of firings across the league, a lot of interesting possibilities have opened up for the San Francisco 49ers.
Head coach Kyle Shanahan could potentially turn a longtime nemesis into a key ally.
The Cleveland Browns unsurprisingly fired head coach Kevin Stefanski after a brutal season in which the team went 5-12. That likely means defensive coordinator Jim Schwartz, who has had Shanahan's goat throughout his career, may now be a free agent.
Whenever Schwartz and Shanahan have gone toe-to-toe over the years, the former Detroit Lions head coach has always seemed to get the better of the offensive play-caller whom many consider a genius.
Between Schwartz owning Shanahan over the years and his infamous handshake debacle with Jim Harbaugh after a 49ers game against the Lions back in 2011, he has not exactly endeared himself to Niners fans.
But if Richard Sherman can become a 49er after how much he terrorized San Francisco as a member of the Seattle Seahawks, then it should be easy for fans to embrace Schwartz.
Of course, likely the only way he would be brought into the fold in San Francisco is if Robert Saleh departed to fill one of the head coaching vacancies around the NFL. Saleh can definitely afford to be patient and take his time after his first head coaching stint with the New York Jets did not go well.
But at the same time, Saleh may be eager to get another chance to prove himself as a head coach after things did not go his way in New York.
If he does, the 49ers will likely cast a wide net in the search for a new defensive coordinator. They have a solid internal option in Gus Bradley, but maybe Shanahan would want to go for an old friend like Raheem Morris who was just fired by the Atlanta Falcons.
Despite Schwartz's success against Shanahan, historically, the 49ers did beat the Browns this season in a cold game on the road. They were mostly able to hold Myles Garrett in check, which is no small feat considering he just broke the NFL sack record.
Schwartz could probably do some pretty nasty things with a defense that should have linebacker Fred Warner and edge rusher Nick Bosa back from injury.
Everyone loves a good enemies-turned-allies story, so maybe Shanahan will go after his nemesis if he has to get a new defensive coordinator this offseason.