"Me, Matt Breida, Tevin Coleman, and I'll take Jeff Wilson," Mostert said.
Notice a pattern? Yes, Mostert named all four of the team's running backs (with apologies to Kyle Juszczyk, who would undoubtedly be in the discussion for the league's fastest fullback).
"Honestly, it could be the guys in the running back room," Mostert said. "I'll take them."
Of course, neither the 49ers nor the Kansas City Chiefs are actually preparing to run a relay this week ahead of the Super Bowl on Sunday (6:30 p.m. ET, Fox), but if they were, you'd be hard-pressed to find two rooms better equipped to do it than the Niners' running backs and the Chiefs' wide receivers.
In San Francisco, it's Mostert, Breida, Coleman and Wilson who form the 49ers' speedy backfield. In Kansas City, it's Tyreek Hill, Mecole Hardman, Sammy Watkins, Demarcus Robinson or Byron Pringle who make up the Legion of Zoom.
"We are the home run team," Watkins said. "We can throw deep. We've got all these track runners, all these thoroughbreds. ... We can possibly be unstoppable."
Both groups have the same illness that plagued "Top Gun" hero Pete "Maverick" Mitchell: the need for speed.
Consider the following:
- The Chiefs' average maximum speed by receivers when they have the ball in their hands on passes this season (including playoffs) is 15.45 mph, highest in the NFL, according to NFL Next Gen Stats. Chiefs wideouts have 11 receptions this season with a max speed of 20 mph, most in the NFL. The Chiefs' fastest man? Hill ran a 9.98 second 100-meter dash at the 2013 Junior College Championships. That time would have been fast enough to qualify for the 100-meter final in the 2016 Summer Olympics.
- The 49ers' average max speed by running backs as ball carriers on rushes this season (including playoffs) is 13.27 mph, the fastest in the NFL. The 49ers' fastest man? Mostert qualified for the 2014 NCAA Outdoor Track & Field Championships with a 10.15-second 100-meter dash.
Leading the way for the Chiefs, of course, is Hill, the man they call "Cheetah" -- the only player on the Madden 2020 video game with a 99 speed rating. Not far behind are Hardman, who clocked a 4.33-second 40-yard dash at the 2019 NFL combine, and Watkins, who ran a 4.43 at the 2014 combine.
Lest anyone think that speed is limited to running in shorts and workout shirts, 49ers defensive coordinator Robert Saleh would encourage you to simply turn on the tape.
"It almost looks like they got their roster from the Olympic relay team and threw them all on the football field," Saleh said. "They're the fastest team by far. To try to compare it to another team would not do them justice, to be honest with you. But, anytime you have speed like that, it naturally will stress the defense."
Kansas City tight end Travis Kelce says speed allows the offense to do "anything we want to do," noting "speed kills in this game." And quarterback Patrick Mahomes, who is in many ways the perfect quarterback to take advantage of that speed with his powerful right arm, said he can't imagine having a faster group at his disposal.
"We've got guys that can roll, guys that really stretch the field," Mahomes said. "It really makes my job a lot easier. We're able to stretch the field vertically and horizontally. You can either take the deep pass and throw it like that or throw it out in the flat, and these guys can all take it 70 yards to the house."
Meanwhile, in San Francisco, the Niners have quietly built a running backs group that uses speed to make up for lack of pedigree. Of the four backs on the roster, only Coleman was drafted, going in the third round in 2015.
During the 2019 season, a running back exceeded 21 mph 19 times. The 49ers accounted for four of those plays, most in the NFL (the Chiefs' Damien Williams also made the list).
Pound for pound, Breida might actually be the fastest, which is why he has gotten some heat from Chiefs fans for also answering to the nickname "Cheetah" (rhymes with Breida). Of all the players in this game, Breida holds the record for fastest recorded speed with the ball in his hands, reaching 22.3 mph on an 83-yard touchdown run against Cleveland in Week 5.
Of course, his teammates are also speedy. Mostert averaged 11.33 mph when crossing the line of scrimmage this season, the fastest among all running backs, with Breida third (10.9 mph) and Coleman eighth (10.46 mph).
"Speed, you can't really match it," Mostert said. "It's hard to match speed, especially with a defense that necessarily doesn't have good speed on the perimeter. You can definitely exploit and take advantage of those opportunities, and I think we've done a great job this year of doing that."
Chiefs defensive coordinator Steve Spagnuolo is tasked with slowing down the Niners.
"What they're really good at is getting you to run east-west and then cutting it back," Spagnuolo said. "They have the speed guys that can do that. ... They're really good at it. We'll have to come up with a couple of things to slow it down."
In a Super Bowl that will be played with the fast-forward button permanently pressed, whichever team first locates the pause button figures to have the advantage.
ESPN Chiefs reporter Adam Teicher contributed to this story.
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