The San Francisco 49ers will square off against the Seattle Seahawks in Week 17 and a familiar face will make his return on Sunday. Upon hearing the news, Kyle Shanahan reacted to Marshawn Lynch signing with Seattle ahead of Sunday's contest.

Last week, the Seahawks lost Chris Carson for the rest of the season due to a hip injury. Along with Carson, C.J. Prosise also broke his arm and was ruled out for the remainder of the season.

As a result, Travis Homer (Seattle's sixth-round pick in 2019) was forced to assume the starting role. With Homer being the only healthy running back on the roster, the Seahawks chose to seek out Lynch and Robert Turbin.

When the Seahawks signed Lynch, many in Seattle rejoiced to have him back with the franchise. On the other hand, Shanahan believes it could be a challenge for Lynch to get adjusted to playing in the NFL again.

“It is a huge challenge,” Shanahan told reporters on Tuesday. “It depends on how much those guys have been working out and stuff like that. I do think it’s a little different with the running back position.

Lynch hasn't played a snap in the NFL since last season with the Oakland Raiders. Provided that, it could some time for him to get acclimated into Seattle's offensive schemes this week.

Regardless of how much he plays on Sunday, it's awesome to see Lynch return to where he succeeded in his career. Even players in San Francisco's locker room were excited to see him possibly return to Seattle before signing with the Seahawks on Monday night.

“That’d be awesome,” Kittle said Monday morning. “I love watching him play. I mean he brings a lot to the table so it’d be an unreal challenge. I’ll let that play out but I’m a fan of it. I would love to see that.”

The respect that Lynch has received from the 49ers goes to show what difference he could make in Week 17. Without a doubt, he won't handle a full workload in his first game back. But it could be enough to provide challenges for San Francisco's defense.