SANTA CLARA -- The 49ers' running back depth knows no bounds.
The group as a whole, when healthy, is an embarrassment of riches that the Dallas Cowboys, San Francisco's opponent on Sunday night at Levi's Stadium who is devoid of efficient and effective runners, certainly wish they had a piece of.
Sure, you can credit coach Kyle Shanahan's scheme for some of the next-man-up success the 49ers have had over the years, but there's an intangible quality only some running backs -- and even fewer rookies -- have that San Francisco continues to identify and hit on.
Rookie fourth-round running back Isaac Guerendo, who has shown flashes of his game-breaking speed at various points throughout the 2024 NFL season, answered the call again after an injury to starter Jordan Mason in San Francisco's 30-24 win over Dallas on Sunday night.
Guerendo rushed 14 times for 85 yards and one touchdown on the ground in place of Mason, who left the game midway through the second quarter after injuring his left shoulder, the same shoulder he injured two weeks prior against the Seattle Seahawks.
While neither Mason nor Guerendo is anywhere near the overall player that reigning NFL Offensive Player of the Year Christian McCaffrey is, there hasn't been much of a drop-off in the team's overall rushing production -- if any at all -- with the third-year and rookie back leading the way -- the latter of which might be the better overall rusher of the two.
Guerendo ran a blazing 4.33-second 40-yard dash at the NFL Scouting Combine this spring, the fastest of any player at the position in his draft class. It's not that the expectations for the fourth-rounder buried on the depth chart to begin the season were high, per se, but there certainly was an eagerness to watch him burn. And a disappointment when he didn't.
San Francisco 49ers
When his early-season opportunities (12 carries for 41 yards in the first six weeks) were pretty average, maybe even underwhelming, the attention shifted fully -- and rightfully -- to Mason. However, with each passing week, Guerendo continued to learn and improve and make the most of his opportunities.
"I think the main thing was being able to play fast, learning from game to game," Guerendo said of his in-season adjustments. "The speed of the game. Just talking about getting off the ball. If I'm slow on that, I'm behind the play. Just having the urgency, it allows me to hit those."
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"I think he's learned from each run he's gotten," Shanahan said postgame. "There's a couple runs earlier in the year that he did alright on, but we grade him pretty hard and everyone pretty hard. He had a couple four-yard runs that we thought he could have got seven yards on. We go pretty hard on him and then you watch how he takes that to practice and everything we've been pushing him with, he's been real coachable.
"He's not a sensitive guy, he's real detailed. He's very poised for a rookie, things aren't too big for him. Didn't get a lot of preseason [reps], but once he got healthy there and throughout this year I feel like he's gotten better each week."
Guerendo's first head-turning moment came in that win over Seattle. With the 49ers leading 29-24 with 1:37 remaining in the game, the rookie blasted through a hole on the right side of the offensive line for a massive 76-yard run to ice the game.
Isaac Guerendo with the MASSIVE run to flip the field late 🤯 pic.twitter.com/k5GQxvr4SO
— 49ers on NBCS (@NBCS49ers) October 11, 2024
Guerendo, wisely, slid short of the goal line in order for the 49ers to run out the clock, even though there was some friendly internal debate about whether or not that was a conscious decision by the rookie or if he got tripped up at the end.
Fast forward to Sunday night, and Guerendo once again broke off a long run with nothing but green grass in front of him, and once again, slid short of the goal line in order to run out the clock.
Guerendo leads the league sacrificing TDs to seal wins 😤 pic.twitter.com/LMaJwWwvLM
— 49ers on NBCS (@NBCS49ers) October 28, 2024
He left no room for debate this time around.
"Yeah 110 percent, I had to make sure people knew on that one," Guerendo said with a laugh."
Isaac Guerendo had to make everyone "110 percent" sure he was taking one for the team on his late run tonight 😅 pic.twitter.com/V1g1PGKXFT
— 49ers on NBCS (@NBCS49ers) October 28, 2024
"Yeah, we told him on this one ... but he listened at least," Shanahan said with a smile. "It's hard to turn that down when you're running in and I'm glad he did it for the second time but this one was much better."
The responsible decision, as difficult as it might have been for the rookie, came after Guerendo scored his first NFL touchdown in the third quarter, which certainly makes it easier.
First NFL TD for the rook 🥹
— 49ers on NBCS (@NBCS49ers) October 28, 2024
pic.twitter.com/MqbUOGKnaK
It's unclear what the immediate future holds for both Guerendo and Mason. McCaffrey, whom the 49ers anticipate returning to practice in some capacity during the bye week, with the likelihood that he will be ready to make his season debut in Week 10 against the Tampa Bay Buccanneers, will reprise his role as the offense's do-it-all weapon. One that quarterback Brock Purdy and Co. will lean heavily on.
This means Guerendo and Mason likely will be relegated to backup and third-string roles, only seeing limited snaps that they hope to make the most of.
And if Guerendo's performance in recent weeks is any indicator, it's that he will be ready for when his number is called.
