Only one player definitely won't feature in the San Francisco 49ers' regular-season finale, and it's the man on whose arm their Super Bowl hopes rest.

Kyle Shanahan confirmed in Wednesday's press conference that starting quarterback Brock Purdy will not play as the 49ers face the Los Angeles Rams in a Week 18 game in which they have nothing to play for after clinching the one seed in the NFC in last week.

It had already been confirmed that Matthew Stafford will not play for the Rams, who are the sixth seed in the NFC playoffs and cannot improve their position. Sam Darnold will start for the 49ers and Carson Wentz for Los Angeles.

While Purdy will sit out, he will practice as if he was preparing to start against the Rams, with Shanahan keen to ensure the 49ers do not treat the game as a "second bye week".

Asked what went into the decision to rest Purdy, Shanahan replied: You can rest seven guys when nobody's hurt if you get two practice squad guys up. We have at least six guys injured right now so I only know for sure we can rest one and so I went with our starting quarterback.

"We're treating this as a normal week, Brock will get half the reps with the ones [on Wednesday] Sam will get the other. I want our team to treat this as Brock going down on the first play of the game. That's why I want them both repping it, I want Brock to get some work this week and that's something I'd like us to be ready for if that unfortunately did happen."

Shanahan knows he must prepare for every eventuality in the postseason, having seen his team's Super Bowl dreams end last year because of an injury to Purdy in last year's NFC Championship Game.

So with injuries limiting the number of starters he can sit, he's using a game week with nothing riding on it to ensure his roster is ready for any possibility, emphatically stating his belief that a second week off would be detrimental.

"What you don't want is two off weeks. We've got to make sure we get something out of this week," he added.

What they get out of it will have nothing to do with the end result but, with Purdy getting the chance to skip a game having suffered a stinger earlier this month, clinching the first-round bye a week early has already proven extremely valuable to San Francisco.

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