SANTA CLARA -- Tight end George Kittle is not just the 49ers' most-dynamic option in the passing game. He also is a huge asset as a run-blocker.

The 49ers don't expect to have the services of their Pro Bowl tight end on Monday night for a key matchup against the Seattle Seahawks, so San Francisco must make some adjustments.

Second-year pro Ross Dwelley saw significant action the past four games with fullback Kyle Juszczyk sidelined with a knee injury. Now, Dwelley will help the 49ers compensate for the loss of Kittle, who could miss multiple games with unspecified injuries to his left knee and ankle.

"Nobody on this planet is George Kittle, so we're not trying to have him go out there and be George Kittle," 49ers coach Kyle Shanahan said on the 49ers Insider Podcast. "But if George can't go, I know we have another good tight end to go out there and do that. Hopefully, we can get the other guys out there, also."

The 49ers expect to get three offensive starters back from injuries for the key NFC West game. Juszczyk is cleared to return, and the club also expects to suit up offensive tackles Joe Staley and Mike McGlinchey together for the first time since Week 2.

In addition, Shanahan suggested the 49ers will activate veteran tight end Garrett Celek from the physically-unable-to-perform list. Celek was productive in practice as he returns from offseason back surgery.

"If it was someone besides George, I'd probably already rule him out and we'd get Celek up because he did have a good week of practice," Shanahan said. "But this was his first week back and I wanted to give him some more time because he hasn't had OTAs or training camp or anything.

"We'll see on Monday, but with George being doubtful and if he ends up not playing, we'll end up getting Celek up, because we need three tight ends available."

The 49ers must make a roster move by 1 p.m. Monday in order to have Celek available to play in the game.

With Kittle unavailable for the game, the Seahawks might not know how the 49ers plan to attack Monday night. That is expected because Shanahan said he is not quite sure, either.

The 49ers own the league's second-ranked running game. Matt Breida and Tevin Coleman will get plenty of touches in the game to see if the best route to victory will be on the ground.

But Seattle has been vulnerable against the pass, too. Jimmy Garoppolo is coming off a 317-yard, four-touchdown performance against the Arizona Cardinals. The past two weeks, the Seahawks' defense surrendered 460 yards passing to Atlanta's Matt Schaub and 335 yards to Tampa Bay's Jameis Winston.

"It depends on how the game plays out," Shanahan said. "We never just go into a game saying, ‘Hey, we're going to air this out.'

"We have the weapons around him. We always have the scheme in that gives us the option to go that way ... And depending what they do, it will dictate how he plays, who he goes to with the ball and how much we throw. Every time Jimmy steps out there, he has that opportunity."

Where the loss of Kittle will likely be most obvious is run after the catch. Kittle is a dynamic threat with the ball in his hands. Dwelley has seven receptions for 28 yards. Kittle leads the 49ers with 46 catches for 541 yards and two touchdowns.

Juszczyk's return comes at a good time because of his contributions as a lead-blocker and as a receiver out of the backfield to take advantage of certain matchups.

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The 49ers could look for their big plays to come from the wideouts. Emmanuel Sanders immediately became a trusted target for Garoppolo in the two games since his arrival in a trade with the Denver Broncos. Rookie wide receiver Deebo Samuel will be asked to carry more of a burden, potentially on third downs.

Also, the 49ers are likely to have veteran Marquise Goodwin active after a strong week of practice. Goodwin, who has 11 receptions for 181 yards in six games, provides another deep threat on the outside for Garoppolo.

How 49ers will compensate without tight end George Kittle vs. Seahawks originally appeared on NBC Sports Bay Area