Garrard tweaked his hamstring during practice Thursday and was limited in Friday's session, feeding into speculation that the Jaguars might be forced to start No. 2 quarterback Trent Edwards in their critical Week 15 showdown with the Colts.
That doesn't appear likely to happen, however. A source with knowledge of the situation said the Jaguars are merely taking precautions with Garrard and the veteran will play Sunday.
Bouman's arrival was more coincidence than anything else. The Jaguars already planned to bring him back as playoff insurance should a roster spot become available, which was the case Friday when they placed cornerback Terrence Wheatley (hamstring) on season-ending injured reserve.
Garrard was receiving treatment Friday and unavailable for comment during the team's open locker-room session.
Bouman served two two-week stints with the team earlier this season. He started Oct. 24 at Kansas City and completed 18 of 34 passes for 222 yards and two touchdowns with two interceptions.
Running back Maurice Jones-Drew is questionable after he tweaked his right knee last week, but he's expected to play in arguably Jacksonville's biggest regular-season game in franchise history. The Jaguars (8-5) can clinch the AFC South title with a victory over the Colts (7-6).
Durant, the team's fourth-leading tackler, injured his groin last Sunday against the Oakland Raiders and missed practice all week. Greene hurt his left shoulder Dec. 5 at Tennessee, missed last week's game and hasn't fully recovered. Sean Considine will start in Greene's place.
The Associated Press contributed to this report.