Dustin Hopkins kicked a go-ahead, 29-yard field goal with 1:40 left in the game and the host Cleveland Browns spoiled the San Francisco 49ers' chance at a perfect season with a 19-17 victory on Sunday afternoon.
Jake Moody had a golden opportunity to allow San Francisco (5-1) to escape with a win, but he missed a 41-yard field-goal attempt wide right with six seconds to play.
Jordan Mason had put the 49ers ahead 17-13 when he rushed for an 8-yard touchdown with 10:58 remaining.
Hopkins made a 50-yard field goal just over seven minutes later to pull Cleveland (3-2) within one, and the Browns' defense followed by forcing a three-and-out to set up the game-winning drive.
Mason was in due to an oblique injury that forced star running back Christian McCaffrey out of the game in the third quarter. The 49ers also lost wide receiver Deebo Samuel, who exited the contest in the first quarter due to a shoulder injury.
Without those weapons, Brock Purdy struggled, completing just 12 of 27 passes for 125 yards with a touchdown and an interception. He took his first regular-season loss as a starter, falling to 10-1.
Brandon Aiyuk had four catches for 76 yards for San Francisco, which was held to 215 yards of total offense.
Cleveland quarterback P.J. Walker had 192 yards and two interceptions on 18-for-34 passing. Amari Cooper hauled in four receptions for 108 yards, while Jerome Ford totaled 84 yards on 17 carries.
After Moody made good on a 25-yard field goal to put the Niners up 10-0 with 7:54 left in the first half, Kareem Hunt put Cleveland on the board with a 16-yard rushing TD that made it a three-point game by the break.
Hopkins moved the Browns in front 13-10 with a pair of third-quarter field goals.
San Francisco moved 84 yards in just five plays on the game's opening drive, taking a 7-0 lead when Purdy found McCaffrey for a 13-yard touchdown.
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