Kyle Shanahan was watching as Jimmy Garoppolo scrambled toward th

e 49ers sideline and Malcolm Smith Color Rush Jersey , rather than safely duck out of bounds, stepped back to his right and took a wicked shot from Steven Nelson.At first, the San Francisco coach thought his quarterback had sustained a concussion.Turns out it may have been a season-ending knee injury.Garoppolo’s left knee buckled just before the Chiefs‘ cornerback delivered a shoulder-to-shoulder blow, and that was the reason he went down so hard. Garoppolo was on the turf for a couple of minutes before he was helped to his feet and eventually carted off late in a 38-27 loss to Kansas City.“We fear an ACL,” Shanahan said afterward. “We’ll find out more tomorrow.”That’s bad news for the banged-up 49ers (1-2), who already lost top running back Jerick McKinnon to a season-ending knee injury and only have two other quarterbacks on the roster.C.J. Beathard took over for Garoppolo with just over five minutes left Sunday, and he appeared to throw a touchdown pass to George Kittle before offensive pass interference wiped it out. San Francisco had to kick a field goal and that wound up being the final margin.Now, Beathard is in line to start next week when the 49ers play the Chargers in Los Angeles, and Nick Mullens could get a call-up from the practice squad to serve as the backup.“Any time you lose your starting quarterback, that’s a big deal. It was when we lost our starting running back https://www.49ersfanshop.com/Robbie-Gould-Jersey , too,” Shanahan said. “Feel for him personally. I know how disappointed he is.”Beathard said he spoke to Garoppolo briefly in the trainer’s room, and what little of their exchange he was willing to repeat made it quite clear the 49ers’ franchise quarterback 鈥?who signed a five-year, $137.5 million extension in February 鈥?expects his season to be over.“I told him I’ll be praying for him and I love him and he just told me to lead these guys,” Beathard said. “I’ve never been in that situation with something possibly that serious. I can only imagine how tough it is for him this early in the season.”It’s also a big blow for the 49ers, who thought they had the pieces to contend for a playoff spot his season. Now, they’ve lost two of their most important offensive pieces, to say nothing of a series of injuries on defense Sunday that left them with a piecemeal backfield.Top cornerback Richard Sherman went down with a calf injury, while backup Tarvarius Moore left with a wrist injury. Strong safety Jaquiski Tartt was inactive with a shoulder injury and free safety Adrian Colbert hurt his ankle, forcing a bunch of backups to play significant snaps.Chiefs quarterback Patrick Mahomes wound up handling them for 314 yards passing and three TDs.“They do a lot of things. They use their personnel well. They have a lot of guys that are interchangeable and have a lot of tools Reuben Foster Jersey ,” said backup safety Antone Exum Jr. “It’s a team you have to stay disciplined on and play your assignment.”Still, the 49ers leaned on running backs Alfred Morris and Matt Breida and the strong arm of their quarterback to mount a comeback. And after Garoppolo’s TD toss to Marquis Goodwin in the third quarter made it 35-24, there was a sense of optimism on the San Francisco sideline.The 49ers were still trailing 38-24 when Garoppolo led them inside the Kansas City 5 in the final minutes. The Chiefs answered with sacks by Allen Bailey and Justin Houston on consecutive plays, then flushed Garoppolo from the pocket on third-and-goal from the 20-yard line.That’s when the San Francisco quarterback headed for the sideline, decided to stay in play rather step out of bounds, and ultimately put the rest of the 49ers’ season in question.“Just like we always do, you show up to work tomorrow,” Shanahan said. “We’ll all be men about it. We’ll grade the tape hard and see what we did wrong. And when we show up Wednesday it’s time to go.“It’s part of the NFL season. It’s what you have to do,” he added. “We all feel for Jimmy. There’s no doubt about it. We dealt with this with our running back, too. It’s part of the NFL. We’re not the first team this has happened to.”___ SANTA CLARA Ahkello Witherspoon Color Rush Jersey , Calif. (AP) — Coach Jason Garrett saw all he needed out of quarterback Dak Prescott on just one drive.Prescott made the most of his brief appearance in the preseason opener for Dallas by throwing a 30-yard touchdown pass to rookie Michael Gallup on his only drive before the San Francisco 49ers rallied with two late touchdowns to beat the Cowboys 24-21 Thursday night.“I thought it was a good drive by our offense, a good mix of run and pass,” Garrett said. “Dak made some good decisions. He made a really nice run too keep the drive alive. We got the one-on-one opportunity down the sideline. Michael made a really good release and it was a good throw and catch.”Nick Mullens threw a 7-yard TD pass to Richie James Jr. with 18 seconds left to cap the comeback. Jeremy McNichols scored on a 1-yard run with 4:24 to go for San Francisco.San Francisco’s Jimmy Garoppolo didn’t fare as well as Prescott in his first game action since signing a $137.5 million, five-year contract this offseason. Garoppolo completed 3 of 6 passes on his one drive.“We’re trying to do something different things and see what works and what doesn’t,” Garoppolo said. “We haven’t been in that situation in a year and you try to get things rolling.”More concerning for the 49ers was the fact that six players left with injuries in the first half with the most concerning ones being shoulder injuries to tight end George Kittle and running back Matt Breida that could sideline them for “some time,” according to coach Kyle Shanahan.“It’s what you scares you about training camp, it’s what scares you about the preseason,” Shanahan said. “You just want the game to end.”Prescott sat out the first exhibition game last season but got one series of action against the 49ers this year and looked sharp. He completed all three of pass attempts and converted a third-and-9 with a 12-yard scramble.He capped his night with the deep ball to Gallup, who beat Jimmie Ward down the sideline. Ward got the start at cornerback in place of Richard Sherman, who is nursing a hamstring injury.With the release of three-time Pro Bowl receiver Dez Bryant and the retirement of 15-year tight end Jason Witten https://www.49ersfanshop.com/C.-J.-Beathard-Jersey , the Cowboys are searching for receiving threats this preseason. Gallup, a third-round pick out of Colorado State, has been impressive so far in camp.“That’s a good feeling,” Gallup said. “Especially for me being so young and being a rookie and everything, I needed that boost of confidence. It was a good feeling.”NATIONAL ANTHEMNo players on either team kneeled during the national anthem, although 49ers receiver Marquise Goodwin did raise his right fist throughout the song. The Niners have been at the center of the protests during national anthem ever since Colin Kaepernick began kneeling two years ago. Eric Reid protested last year but both players are no longer with the team. Linebacker Eli Harrold also kneeled during the anthem the past two years but stood to start this season.INJURIESThe Niners had a parade of injuries early, starting with LB Malcolm Smith limping off with a hamstring issue on the opening drive. TE George Kittle and backup RB Matt Breida left with shoulder injuries. Thomas and backup tackle Garry Gilliam were sidelined by concussions and Harrold had a lower leg injury.Cowboys OL Marcus Martin limped off the field in the second half with a toe injury, S Marqueston Huff left with a groin injury, and WR Marchie Murdock had an ankle injury.NOTEWORTHY PERFORMANCESJoe Thomas got the start at linebacker for Dallas in place of Sean Lee and delivered an interception against C.J. Beathard on a tipped pass by Kavon Frazier. … Cowboys rookie RB Bo Scarbrough had a 28-yard run and scored a 1-yard TD in the second quarter. … James had four catches for 46 yards and fellow rookie Dante Pettis caught a 53-yard pass .HELMET FOULThere was one penalty under the new rule prohibiting players from leading with their helmets. San Francisco LB Elijah Lee was called for the infraction on a tackle against Scarbrough in the third quarter.NEXT UPCowboys: Host Cincinnati on Aug. 18.49ers: Visit Houston on Aug. 18.