SANTA CLARA — Nick Bosa had just sacked Geno Smith with 9:26 to play Sunday in the third quarter and the 49ers leading the Seahawks 10-6 when he left the game with a left oblique injury.
Bosa had a half-sack earlier in the game and was ubiquitous throughout, showing no effects of a right hip/oblique injury that limited his practice time all week and showing the form that made him the 2022 NFL Defensive Player of the Year.
As the NFL’s highest-paid defensive player paced the sidelines the rest of the way, the Seahawks ran 30 plays, gained 183 yards, scored two touchdowns and left Levi’s Stadium with a 20-17 win over their NFC West rivals.
Up to the point Bosa was injured, Seattle had run 29 plays, gained 106 yards and had field goals of 52 and 57 yards by Jason Myers.
“Brutal, brutal,” Bosa said at the postgame podium. “The most important time in the game for me to be out there I wasn’t able to be. I hate missing time. That’s why I pushed through last week. Hopefully it’s not too long.”
Bosa made it wire to wire in the 49ers’ 23-20 win at Tampa Bay, not coming alive until late with a key sack and two big stops on running plays. He’d been injured during the week of practice leading up to that game, which led to an extremely limited week preceding Seattle.
Making it hurt all the more is that Bosa, instead of having one strained oblique, now has a matching set.
“I guess I was compensating,” Bosa said. “I pushed through last week and it happened to my other oblique. I’ll see what I’m feeling like tomorrow.”
Up next for the 49ers are two difficult venues against playoff contenders in cold weather sites — Green Bay (7-3) and Buffalo (9-2). Whether Bosa can get himself healthy enough to play in either of those games will be determined by team doctors and his own pain tolerance.
Bosa showed he could tolerate a lot last week, but Sunday was different.
“That’s why I had to stop playing,” Bosa said.
Before he went out, the 49ers’ pass rush was finally looking as if it would give Bosa some help. Leonard Floyd finished the game with 1 1/2 sacks, with one coming after Bosa was injured. Yetur Gross-Matos, signed during free agency, had a solid debut and also had a sack of Smith.
But Smith made big plays in Bosa’s absence with his arm and especially with his legs.
With Seattle at the 49ers’ 37 and facing a second-and-13 with 50 seconds remaining after Floyd’s sack, Smith found a running late and scrambled 16 yards to the 21-yard line. He completed an 8-yard pass to Jaxon Smith-Njigba before delivering the final crushing blow.
Smith escaped one last time to his left and scrambled in from the 8 for the game-winning score with 12 seconds to play.
“We were in man coverage so that means it’s going to be hard to get to him if he escapes because everybody’s got their back to him,” linebacker Fred Warner said. “Got to be better.”
The 49ers defense had its moments even without Bosa, with Dee Winters and Ji’Ayir Brown stopping Zach Charbonnet on a fourth-and-1 with a 17-13 lead and 4:06 to play.
But the 49ers offense couldn’t bleed the clock to put away the win, giving Smith and Co. one final chance to drive 80 yards in 11 plays and win the game.
While fans as well as the television cameras followed a pensive Bosa closely on the sideline, NFL players and coaches aren’t wired that way. At least not publicly.
“We don’t think about that in the moment,” Shanahan said. “It helps when Nick’s out there, especially with the last drive and stuff. I thought we had a couple of opportunities to get (Smith) and we did get a sack, but those two scrambles on the last drive hurt us.”
Gross-Matos conceded being without Bosa put the 49ers at a disadvantage although one they could have overcome.
“It definitely hurt,” Gross-Matos said. “I wanted a different result for him. Wanted to win it for him and didn’t get the job done.”
Cornerback Isaac Yiadom expressed surprise that Bosa wasn’t in the game.
“I didn’t realize that Bosa left so I can’t really speak on that,” Yiadom said. “No matter who’s out there, we’ve got to finish games.”
Linebacker De’Vondre Campbell chalked it up to the life of attrition in the NFL.
“We all know what Bosa is — former defensive player of the year,” Campbell said. “Any time you lose a player of that skill set of course it’s going to affect you a little bit, but that ain’t no excuse. We’ve got to finish.”
The loss left the 49ers at 5-5, the same as Seattle and the Los Angeles Rams. Arizona is a game up at 6-4 with a bye and plays the Seahawks next week. After losing already to the Rams and Cardinals, a division title will be a challenge. Bosa already seemed to be preparing for a 49ers push to sneak into the playoffs rather than winning the No. 1 seed they’ve been for the last two years.
“It’s kind of hard to think about the big picture right now but we have a lot of games left,” Bosa said. “All we’ve got to do is get in the dance and I definitely still have confidence.”
