ATHENS, Ga. (AP) -- Quarterback Aaron Murray said Tuesday he is spending extra practice time with players promoted from the scout team and No. 7 Georgia tries to compensate for injuries that have forced dramatic changes at wide receiver and tailback.
Last week's 34-31 overtime win at Tennessee was costly.
Tailback Keith Marshall and wide receiver Justin Scott-Wesley were lost for the season with right knee injuries that will require surgery.
Another receiver, Michael Bennett, also hurt his right knee and had arthroscopic on Tuesday to repair torn meniscus.
Bennett won't play in Saturday's game against No. 25 Missouri but is expected to return this season, according to Georgia director for sports medicine Ron Courson.
Scott-Wesley also had surgery to repair meniscus in his right knee. Both Scott-Wesley and Marshall will have surgeries to repair torn anterior cruciate ligaments in their knees and are expected to recover for the 2014 season.
Coach Mark Richt said tailback Todd Gurley, who didn't practice on Tuesday, is doubtful to play this week. Gurley missed the Tennessee game with a left ankle sprain.
Gurley's status could be upgraded on Wednesday, when Richt said ''we'll see how he runs just straight ahead.''
''Is he going to play this game?'' Richt asked. ''He could. We're not counting him out, but we have to prepare as if he won't play.''
The injuries are mounting for a Georgia team that already lost top receiver Malcolm Mitchell to a season-ending knee injury in the opening loss to Clemson.
''It stinks,'' Murray said Tuesday.
Gurley ranks third in the Southeastern Conference with his average of 112.5 yards rushing while sharing time with Marshall.
After Marshall hurt his knee in the first half last week, freshmen J.J. Green and Brendan Douglas had to fill in. Green ran for 129 yards on 17 carries. Douglas added 25 yards rushing and a fourth-quarter touchdown.
The performances by Green and Douglas provide confidence Georgia (4-1, 3-0 SEC) can overcome the loss of Marshall. Richt said he is confident Gurley will be ready at least by the Bulldogs' Oct. 19 game at Vanderbilt.
It may be more difficult for Georgia to overcome the losses of Scott-Wesley and Bennett.
Richt said Michael Erdman and Blake Tibbs were summoned from the scout team to add depth at receiver. Murray said he's working with freshmen Reggie Davis and Kenneth Towns.
''Those young guys, especially the receivers, are going to have to work a little extra hard this week,'' Murray said. ''We've already started getting some extra time in yesterday working on some routes after practice and we're going to have to do that every day this week. Working before practice, during practice, and after practice to make sure our timing is on.
''I've got to make sure they know what I'm looking for out there.''
Senior Rantavious Wooten led Georgia with a career-best six receptions for 38 yards and two touchdowns - including a tying catch with 5 seconds remaining in regulation - at Tennessee.
Junior Chris Conley leads Georgia with 20 catches for 318 yards and three touchdowns.
''We've had a lot of adversity in this position this season,'' Conley said. ''It's kind of been the story that when one guy goes down, another guys steps up.
''We've had quite a few guys go down but I don't think it's going to change the way we do things. I think just another young guy is going to have the chance to step up, and you are going to be hearing some new names.''
Georgia has leaned on its offense as its defense has allowed 32.2 points per game to rank last in the SEC. Missouri (5-0, 1-0) is scoring 46.6 points per game, second in the league.
A depleted Georgia offense may be asked to find a way to keep pace in another high-scoring game.
''Games like this, we'll see what kind of character this team has, what these guys are really made of,'' Conley said. ''Obviously there are a lot of new people. Obviously people are in different spots and places where they're not as comfortable. You're going to be expected to perform at a high level.
''There are no excuses that will be made. No one in here is getting a pass on anything. You still have to be prepared to play a great football game against a good team on Saturday.''