49ers RB Raheem Mostert delivers a stiff-arm to remember, even if it didn’t count

One of the most entertaining plays of the first half of tonight's game between the San Francisco 49ers and Los Angeles Rams wound up being called back due to a penalty, but the highlight is so fun to watch that it's worth taking another look.

The play in question came from 49ers running back Raheem Mostert, who delivered a powerful stiff-arm to the face mask of linebacker Micah Kiser on a second-down run late in the second quarter. The run was nullified when wide receiver Brandon Aiyuk was flagged for holding, but the footage was certainly enough to get fans excited.

When Mostert wasn't stiff-arming linebackers to the ground in the first half, he was playing a big role in helping the 49ers build a 21-6 halftime lead. Mostert finished the half with 64 yards on 16 carries, with seven of those carries coming on the same drive as the stiff-arm. The 49ers scored on a two-yard pass from Jimmy Garoppolo to Aiyuk to finish the drive, which stretched 75 yards on 13 plays.