WESTMINSTER, Md. -- Baltimore Ravens defensive tackle Haloti Ngata was carted off the field Sunday with an injured right leg after getting caught in a pileup during a full-contact drill.

Ngata was on the ground for several minutes before limping with assistance to the sideline, where he was then driven off the field.

"We don't think it's serious, but we've got to find out as we go," Ravens coach John Harbaugh said.

Ngata's injury was the latest in a long list during Harbaugh's first week of training camp.

Running back Willis McGahee didn't practice because of a lower left leg injury, and offensive tackle Jared Gaither also didn't practice after spraining his right ankle Saturday.

"He woke up and it was swollen," Harbaugh said of Gaither, who is vying to fill the void left by the retirement of Jonathan Ogden. "They're evaluating it still."

Adam Terry moved over to Gaither's left tackle spot, with reserve Mike Kracalik inserted as the starter on the right side in Terry's place.

Rookie Ray Rice took over for McGahee.

Others not practicing: safety Ed Reed (physically unable to perform list, undisclosed injury); cornerback David Pittman (PUP, foot); running backs Cory Ross (arm) and P.J. Daniels (cramps); and offensive tackle David Hale (undisclosed).

Cornerback Chris McAlister, who underwent offseason knee surgery, passed his physical and began practicing after being activated from the non-football injury list.

Also, cornerback Fabian Washington and fullback Le'Ron McClain were activated from the non-football injury list after passing a conditioning test. Tight end Daniel Wilcox (offseason toe surgery) and wide receiver Demetrius Williams (lower left leg) remain on the PUP list.

Cornerback Samari Rolle has been excused from practice following his father's recent death.

"The timetable is Samari's right now," Harbaugh said.

Copyright 2008 by The Associated Press