The Dolphins' quarterback battle just took a sudden turn.

Former Pro Bowler David Garrard, who was projected to start Friday’s preseason opener against Tampa Bay, will undergo arthroscopic knee surgery and miss an unspecified amount of time, reported Jeff Darlington of NFL.com.

Garrard, 34, hasn’t thrown a pass in an NFL game in 18 months and missed all of 2011 with back surgery.

The mantle of starter now likely falls to incumbent Matt Moore, who completed 60.5 percent of his passes last season for 2,497 yards with 16 touchdowns against nine interceptions. Moore is a favorite in the locker room and led the team to a 6-3 record down the stretch after a disastrous 0-7 start.

Also battling for the starting job Week 1 against Houston is rookie signal caller Ryan Tannehill. The eighth overall pick in April’s NFL draft has received rave reviews during preseason practice and was even nicknamed “the people’s choice” by Garrard. Tannehill also has an advantage, as his former coach at Texas A&M, Mike Sherman, is the Dolphins' offensive coordinator.

If Garrard misses any extended time, it could mean more early playing time for Tannehill, something that has worked great for some rookie NFL quarterbacks (SEE: Ryan, Matt) or ended very poorly (SEE: Smith, Akili).

No offense to former Penn State Nittany Lion and Delaware Blue Hen Pat Devlin, but he has a better chance of making the practice squad than being under center Week 1.

For more up-to-the-minute news and analysis on the Miami Dolphins from blogger Dave Carey, follow @CBSSportsNFLMIA.