FOXBORO, Mass. -- In a 24-17 victory over the New England Patriots, the St. Louis Rams showed coach Mike Martz that the defense played with plenty of heart. What they are running out of, though, are healthy limbs.

	Dexter McCleon, right, gets tackled by Kevin Faulk after making this first-quarter pick.

The Rams' defense, perhaps the most improved in football thanks to Martz's overhaul during the offseason, suffered four significant injuries on Sunday night. Defensive tackle Damione Lewis, the team's top draft choice, will undergo surgery Monday to repair a broken metatarsal bone in his right foot. Lewis is out for the rest of the regular season although there is an outside shot he could be available late in the playoffs.

Defensive end Leonard Little, who has more than filled in for Kevin Carter's lost presence with nine sacks in nine games, will undergo an MRI for medial collateral ligament damage in his left knee. Linebacker Mark Fields aggravated an ankle injury he suffered a week ago and left the game in the third quarter. Strong safety Adam Archuleta suffered a concussion and an ankle injury on the same play that Little was injured in the second quarter.

Archuleta's status for next Monday's game against the Tampa Bay Buccaneers is in question, although he may have the least serious of the four injuries on defense.

"We did get banged up in this game," Martz said. "We got some guys who came off the bench and did a real good job for us."

How thin were things for the Rams' defense? They had to play the second half with only four healthy linebackers, including O.J. Brigance, who ended up replacing Fields. What's so strange about that? Brigance was signed only last Monday.

"We're thin at linebacker as you can see," middle linebacker London Fletcher said. "When Fields went down, the coaches told me that I couldn't get hurt.

Fletcher responded by having a monster game. He led the Rams with 11 tackles. He stripped a fumble from the hands of Patriots halfback Antowain Smith at the Rams' 3 in the final minutes of the first half. The Rams marched 97 yards to take a 14-10 lead and control of the game before throwing an interception.

	“	We're thin at linebacker as you can see. When Fields went down, the coaches told me that I couldn't get hurt. ”
		— London Fletcher, Rams linebacker

Then in the second half, Fletcher read the eyes of quarterback Tom Brady in a two-deep zone and picked off a pass in the middle of the field that snuffed out another drive.

Prior to his injury, Fields also was having one of his best games. He had eight tackles in the first half.

"I was on fire," Fields said. "I thought my ankle was finally healthy and it felt good and then I hurt it again. I've got to get it right for the Monday night game."

Losing Little and Lewis, though, will hurt the Rams' pass rush. Lewis was drafted for his ability to bring inside pressure on the quarterback, and although he wasn't starting, he was still valuable in the rotation. Little plays on passing downs and provides instant quarterback pressure.

The Rams also lost wide receiver Az-Zahir Hakim with an ankle injury. Ricky Proehl handled his assignments and Yo Murphy was the fourth receiver used in four-receiver sets.

Brady gets one more start
Patriots fans shouted "Drew!" to Drew Bledsoe as he headed to the locker room after the game. That group of fans did not include coach Bill Belichick, who doesn't appear to be ready to bring his $103 million quarterback back to the starting lineup.

	Brady

Bledsoe, who is still 10 pounds under his playing weight following internal complications from a cut blood vessel in his chest, was Tom Brady's backup against the Rams. Belichick probably will start Brady against the Saints next Sunday, but the days of Drew might be nearing.

Brady worked only short, conservative stuff against the Rams. He completed five consecutive passes for 65 yards in a fourth-quarter scoring drive that cut the Rams' lead from 14 points to 24-17. Those five completions inflated his numbers. Take away those five completions, and Brady was 14-for-22 for 114 yards and two interceptions.

As Bledsoe's replacement, Brady is an amazing 5-3 and extremely popular among Patriots fans, so it's unlikely a change will come next week. The Patriots conclude a three-game homestand against the Saints.

But Brady's numbers are starting to deflate. He had only 107 yards on 21 attempts in a 21-11 victory over Buffalo last week. Three weeks ago, he threw four interceptions against the Broncos.

"We had some deep stuff called and they were back there and couldn't get it thrown," Belichick said. "A couple of times we had pressure. We had our chances and we need to execute better. We had some dropped balls, missed some, had a little pressure, gave up some plays on defense. We just came up a little bit short."

John Clayton is a senior NFL writer for ESPN.com.