On the first play of the Niners' second drive, quarterback Jimmy Garoppolo found Mostert breaking over the middle against rookie linebacker Isaiah Simmons on an angle route and hit him in stride, and Mostert raced 76 yards to the end zone, putting the 49ers up 10-0 with 9:53 left in the first quarter.
According to NFL NextGen stats, Mostert reached a top speed of 22.73 mph on the play, the fastest speed reached by a ball carrier over the past three seasons (since the start of 2018). Mostert replaces his former teammate Matt Breida at the top of the list, who reached 22.30 mph on his 83-yard TD run in Week 5 of the 2019 season.
The play almost certainly brought back some bad memories for the Cardinals as it was almost the exact same design that Niners running back Jeff Wilson Jr. beat Chandler Jones on for a game-winning touchdown the last time the two teams met at Levi's Stadium.
Mostert, who emerged as the team's primary running back down the stretch last season, made the first start of his career after playing a reserve role in his first five seasons. The touchdown catch was a career-long for Mostert.