It shouldn't have surprised anyone that two defensive teams such as the Baltimore Ravens and New York Giants clashed at the Super Bowl. Attrition of skilled players on offense robbed the NFL of a lot of touchdown makers.

Knee problems took receivers Rob Moore, Kevin Dyson, Joey Galloway, Raghib Ismail, Michael Westbrook and Bobby Engram. A rare foot problem sacked Duce Staley, Terrell Davis, Errict Rhett, Trung Canidate and Jeff Blake. That's a lot of skilled talent standing around the sidelines on crutches.

	Garrison Hearst returned to practice last November.

Offseason programs have hit the short vacation mode for the next couple of weeks, but the preseason reports are encouraging. Maybe it's the optimism that months of practicing without pads and hitting, but if the trend continues, defenses might have tougher challenges. Competition will be intense for Comeback Player of the Year.

Of course, last week was a setback. The Chiefs lost receiver Sylvester Morris for the season with a torn ACL and Ike Hilliard's delay in getting foot surgery makes him a question mark for the Giants' first-regular season game. And there still isn't a definitive word from Jacksonville on how long it'll take receiver Jimmy Smith to reach full strength following three abdominal procedures.

Still, some of the comeback stories are compelling.

In San Francisco, 49ers coaches are pinching themselves from what they see of Garrison Hearst, who has missed most of the past two seasons because of an ankle weakened by an area of dead bone. Hearst did so well at the team's June mini-camp that they rewarded him with a spot on the first team.

The Niners aren't going overboard, but Hearst ran with power and authority. Even young running backs Kevan Barlow and Paul Smith were impressed. Hearst's return is critical for the 49ers, who let Charlie Garner go to the Raiders in free agency. Barlow is talented enough to be considered the running back of the future, but Hearst can buy him time to grow into the job instead of being rushed.

Plus, Hearst is a much needed leader on a team that has gone from one of the league's older teams to one of the youngest in a short period of time. With all of the improvements on defense over the past two drafts, the 49ers have a chance of being a playoff contender this season. Having Hearst in the backfield for even 10 to 15 plays a game is vital.

The receivers coming off last year's knee injuries are right on schedule. Perhaps the most important story, though, comes from Philadelphia.

Staley, the Eagles' halfback, is the first of a rapidly growing number of players coming back from a serious malady just named. He was the first of about a half dozen players coming back from a weird foot problem known as Lisfranc.

Without getting too medical here, Lisfranc is what happens to your foot if you fall off a horse with a foot in the stirrup. The twisting creates a separation the width of a dime in the top of the foot that trainers and team doctors started pinning down last season.

For years, players lumped those injuries with those painful turf toes, the gross hyperextension of the toe. Turns out Lisfranc is a ticking timebomb for skilled players. Eventually the arch falls, and in a matter of time the player loses the ability to explode. Soon, they are out of the league and into retirement.

That's why Staley's recovery is so important to a lot of players who are just finding out that is their problem. Rhett suffered one. After months of checkups, Davis found he had not only a Lisfranc but he also had a stress fracture. Blake's shattered right foot had one. So did Canidate of the Rams. Falcons linebacker Keith Brooking pushed his recovery from one a little too much in recent weeks and feels a little sore.

Staley's positive return to the Eagles' backfield this month was a good sign from the growing list of Lisfranc.

"I went into this blind thinking I'm the first to get it," Staley said. "Errict had his right after mine. Remember, I got up and walked off the field after I got my injury. As I kept going up the sidelines, it got worse and worse."

A couple things were learned during Staley's recovery. First, a surgeon inserted a plate on the top of the foot and locked them in with screws. That brought stability back to the top of the foot. No major surgery was needed.

The second part of the recovery was the most vital. Under trainers' orders, Staley wasn't allowed to run for eight weeks. Then they took the screws out. He wasn't allowed to run another eight weeks.

"They didn't want me to do anything. They wanted the foot to heal," Staley said.

In Denver, Davis also waited until late May to start running. That patience may also be the key to his recovery.

"You will gain a little weight during that time because you won't do anything," Staley said. "They kept putting my foot in a boot."

Eventually, Staley worked on little things. He was encouraged to drop marbles on the floor and pick them up with his right toes.

"I'd pick them up and put them in a cup," Staley said. "That's supposed to strengthen that joint. Now, I can pick up a marble and shoot it with my toes."

While that new trick amused him, the biggest test was the June mini-camp. Staley was back to running at full speed. He was making cuts. The pain was gone.

If his and other recoveries work, it will be a huge advance in football medicine. Remember how ACL tears used to take two years to heal. Now, recovery can be six to eight months. Remember how Achilles' tendon tears were career-enders. Now, guys are back the next season.

Training camp will be a more grueling test. But so far, so good.

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