49ers QB Brock Purdy's legs 'the difference between us winning and ...

Eric Williams

NFC West Writer

SANTA CLARA, Calif. — The narrative was that San Francisco 49ers couldn't come from behind in the Kyle Shanahan era.

But during this season's playoffs, they've dispelled that notion with two big-time comeback wins to advance to the Super Bowl.

On Sunday, one catalyst for San Francisco's 34-31 victory against the Detroit Lions was the legs of quarterback Brock Purdy, who finished with 48 rushing yards. 

"It's just amazing because I don't think too many people know how fast and elusive Brock is until he gets to running," Deebo Samuel said. "I think I kind of messed up one of his touchdowns trying to get a lead block, and he ran right into me and bounced off. I feel like If I would have made that block, he probably would have scored." 

According to Next Gen Stats, Purdy converted three first downs on scrambles and completed 3-of-4 passes for 41 yards and three first downs on passes when he scrambled outside the pocket.

The second-year quartervack said getting outside the pocket and using his legs is nothing new.

"My job is to distribute the ball to guys that are open," he said. "Then if something is not there, especially in this kind of game, you got to find a way.

"I feel like throughout my life I've scrambled here and there. Since I've been here, I feel like I haven't done it a whole lot. Obviously tonight, I was just trying to keep the chains moving, keep the ball moving forward and then give our team some momentum and some juice."

Did Brock Purdy prove he's a top QB in the NFL?

Purdy will never be mistaken for Lamar Jackson or Josh Allen. The Iowa State product finished with just 144 rushing yards during the regular season. Of course, when you have explosive runners like Christian McCaffrey and Samuel, it makes more sense to design plays to get them the ball in space. 

"Sick," tight end George Kittle said when asked about Purdy scrambling. "Do it more … just don't get hit. Like, maybe tuck the ball a little faster. He scampers — I think that's the best way to describe it. You ever seen one of those little water dragons running across the water? Like, that's what I envision every time he's running with the football."

However, San Francisco offensive lineman Colton McKivitz says Purdy is a surprisingly good runner who adds another dimension to his team's offense.

"It's him trusting his legs," McKivitz said. "The more you can do. There's guys like [Patrick] Mahomes that we're going to see. Obviously, Lamar, he's a lot slower (laughs). But it gives us another threat and just that extra little thing that the defense has to account for with a guy that can run."

While Kyle Shanahan won't be building an inventory of designed runs for his QB, the head coach was thankful for the plays Purdy made scrambling. 

"I thought it was the difference between us winning and losing," Shanahan said. "He made some big plays with his legs, getting out of the pocket, moving the chains on some first downs, some explosives.

"He competed his ass off today. Wasn't easy for any of us. He kept grinding and was unbelievable there in the second half." 

Eric D. Williams has reported on the NFL for more than a decade, covering the Los Angeles Rams for Sports Illustrated, the Los Angeles Chargers for ESPN and the Seattle Seahawks for the Tacoma News Tribune. Follow him on Twitter at @eric_d_williams.

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