During a crucial stretch of the third quarter last Saturday, Duke was methodically driving down the field, and all Navy's top tackler, Rob Caldwell, could do was watch from the sideline.

Earlier, Caldwell had split three stitches across the bridge of his nose making a tackle, and team doctor Jeff Fair was furiously fitting a plastic, protective piece over Caldwell's cut to stop the blood.

"It was killing me not being out there," Caldwell said, who first injured his nose while making a tackle in a loss to Stanford three weeks earlier. "I kept watching the big screen to see what was going on and the doctor was yelling at me to keep my eyes on him so he could fix what was wrong. I didn't care about the blood. I just wanted to get back on the field."

Caldwell reentered the game in time to force the Blue Devils to settle for a 43-yardfield goal and finished the game -- a 28-21 victory, Navy's first of the season -- with a game-high 14 tackles. That gave him 41 tackles this season, an average of 13.7 per game, which ranks fifth in Division I-A.

Tomorrow afternoon at Navy-Marine Corps Memorial Stadium, Caldwell will attempt to slow an Air Force team that, despite a 2-3 record, averages 29.4 points per game. The Falcons average 250.8 yards on the ground and 171 yards through the air.

Injuries have never been much of a deterrent for the 6-foot, 222-pound Caldwell.

"I knew Rob was a special player when in one of our first games during his senior year he broke his hand early in the game and still had 18 tackles," said Wally McCormack, who coached Caldwell at Andrean High School in Merrillville, Ind. "He's a mauler. There are tough kids, and then there's Rob. The rest of the season, he just put a cast on and went out there and led us to the state championship game. He would have been our best running back, too, but we couldn't find a way for him to carry the football with a cast on."

"People told me that when I signed Robbie up for Pop Warner football when he was in third grade that he shouldn't play because he was too small and he'd get hurt," said Debbie Caldwell, Rob's mother. "And you know what he did? He went out there and had nine sacks that season. He wasn't afraid to go up against big kids and take them down."

Caldwell has used the same mentality since arriving at the Naval Academy in 2003. He did not play as a freshman after breaking his left leg and injuring his ankle during preseason practice. As a sophomore last season, he worked his way into the starting lineup on special teams and backed up standout linebackers Lane Jackson and Bobby McClarin, who combined for 209 tackles to help Navy go 10-2, its most victories in 99 years.

"Rob has always had that warrior mentality you need to play linebacker," Coach Paul Johnson said. "He's tenacious and finds a way to get to the football. I think the big thing with him was he had to wait his turn because who was ahead of him."

Caldwell teams with juniors Jake Biles, Tyler Tidwell and David Mahoney to form a linebacking corps that has recorded 103 of the team's 257 tackles. In each of the past eight seasons, a safety has led Navy in tackles.

"When I'm out there, I just try to get to the ball as quick as I can," said Caldwell, who also leads the team with five tackles for a loss and is tied for the team lead with two sacks. "I find the gap and get through it."

Tomorrow, those gaps will be harder to find.

"We have to play much better if we are going to have a chance to beat Air Force," Johnson said. "Air Force is a much better football team than Duke. There's no question about that."