Instead, his decision to put the ball in Jimmy Garoppolo's hands backfired, giving the Seattle Seahawks plenty of time to rally for a game-winning field goal that tightened the NFC West race significantly.
With a chance to drive to the winning score or burn precious time off the clock, Garoppolo threw three straight incomplete passes late in overtime, setting the stage for Russell Wilson to put the Seahawks in position for Jason Myers' 42-yard kick that handed San Francisco a 27-24 loss for its first defeat of the season Monday night.
"It's a little gut check taking this L tonight," defensive tackle DeForest Buckner said. "But we're going to bounce back."
The 49ers (8-1) had their chance to win in overtime after Dre Greenlaw intercepted a pass from Wilson at the 4 on the opening drive of the extra session and returned it to the Seattle 49.
San Francisco then drove down to the 29 before Raheem Mostert was stopped just short of a first down on third-and-2. Fill-in kicker Chase McLaughlin, signed last week when Robbie Gould injured his quadriceps in practice, missed badly to the left after making all three tries in regulation.
"Just rushed it a little bit, hit it a little high and unfortunately missed it," he said.
The Niners then forced a three-and-out and took over at their own 20 with 1:50 remaining and Seattle out of timeouts. With San Francisco holding a two-game lead in the loss column over the Seahawks (8-2), Shanahan could have played it safe and made sure to take some time off the clock to ensure at least a tie.
But he called for a pass play on first down that went incomplete to Ross Dwelley. Dante Pettis then dropped a pass over the middle on second down before the Niners took a deep shot to Deebo Samuel on third down that was broken up by Shaquill Griffin.
"The first down, we expected to get a completion, but we got a tipped ball," Shanahan said. "Second down, we have to be able to throw and catch there between Dante and Jimmy. And then it's tough on third-and-10. Definitely didn't want to run it on third-and-10. Wanted to go for the first down. Definitely wish we had taken more time off the clock but was counting on us catching one of those balls."
Instead, the 49ers used up just 14 seconds and gave Wilson plenty of time to lead a game-winning drive he keyed with an 18-yard scramble on third-and-3.
"He's one of those guys when you're rushing, he's looking and if he doesn't have a guy open, he's looking to create a play and looking for some rush lanes to open," Buckner said. "He got us a couple of times. Up front we have to do better at knowing where we're at in our rushes."
But the main problem this night wasn't the defense or even the kicker. San Francisco was unable to do much of anything offensively against a defense that has struggled in recent weeks.
The running game was limited to 3.2 yards per carry and the passing game was mostly ineffective, with injured tight end George Kittle sidelined and receiver Emmanuel Sanders leaving in the first quarter with injured ribs.
Garoppolo went 24 of 46 for 248 yards, one touchdown and one interception; he was plagued by several drops from his receivers and bailed out by a few by Seattle defenders as well. Garoppolo was also sacked five times as Jadeveon Clowney and the Seahawks' front dominated San Francisco even with starting tackles Joe Staley and Mike McGlinchey back from injuries.
Garoppolo lost two fumbles on sacks, including one that Clowney returned 10 yards for a score.
"We just had too many self-imposed mistakes, and that's what hurt us," Garoppolo said. "When you put yourself behind like that, it's hard to catch up."
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