KANSAS CITY, Mo. -- Coach Kyle Shanahan suggested the 49ers’ initial plan is to promote quarterback Nick Mullens from the practice squad to take the roster spot that will open with Jimmy Garoppolo’s expected season-ending injury.
“I’m definitely happy with the guys we got,” Shanahan said after the 49ers' 38-27 loss to the Kansas City Chiefs.
The 49ers believe Garoppolo sustained an ACL tear in his left knee. An MRI on Monday is expected to confirm the extent of the injury.
The 49ers began the regular season with quarterbacks Garoppolo and C.J. Beathard on the 53-man roster and Mullens, a second-year pro, on the practice squad. If the 49ers promote Mullens to the active roster, they can be expected to sign a young player to the practice squad.
“We’ll have to do something,” Shanahan said. “We only have two guys on our roster, so we’ll add another guy to the practice squad or bring in a third. We’ll definitely want to have three guys in our building.”
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Beathard attempted only one pass after entering in place of Garoppolo late in the game. He threw an apparent 7-yard touchdown pass to tight end George Kittle, but a questionable pass-interference penalty on fullback Kyle Juszczyk nullified the fourth-down play. The 49ers opted to send out Robbie Gould for a 35-yard field goal on the fourth-down re-play.
During the preseason, Beathard completed 27 of 45 passes (60 percent) for 346 yards and no touchdowns with one interception. Mullens completed 31 of 43 attempts (72.1 percent) for 396 yards and one touchdown with three interceptions.
Undrafted rookie Jack Heneghan served as the 49ers’ fourth quarterback during camp. He got into the final preseason game and completed 8 of 9 passes for 58 yards.