Indianapolis Colts safety Bob Sanders

In Larry Coyer's first season as defensive coordinator, the defense ranked eighth in points allowed (19.2) and played a major part in helping the Colts win their second AFC title in four years.

There's also plenty of room for improvement after yielding 126.5 yards rushing, 24th in the NFL; finishing in the middle of the league in sacks (34); and 15th in interceptions (16). Indy also had 92 defensive penalties, the most since 2005, and couldn't stop the Saints in the second half of the Super Bowl.

With one full season -- and a second full offseason -- to learn Coyer's aggressive system, the Colts have confidence and continuity.

"When you're on the field, just being comfortable with everyone goes a long way," defensive captain Gary Brackett said. "It goes right to the success of your team. I think we should develop a little more in the system, and it's like coach (Tony) Dungy always said, the second year is when you increase your football IQ."

It's not just smoke and mirrors.

Indy, long known as an offensive powerhouse, has made a huge investment in its defense recently.

Six players -- Brackett, Antoine Bethea, Dwight Freeney, Kelvin Hayden, Robert Mathis and Sanders -- have signed contracts worth a combined $242.5 million since 2006. The deals for Sanders and Freeney also were the most lucrative at their position at the time.

Now the Colts are hoping it will pay off, though the tough part will be finding a spot for everyone.

Cornerbacks Jerraud Powers and Jacob Lacey combined to make 21 regular-season starts in 2009 and were impressive as rookies, but they'll vie for the starting job opposite Hayden. Whoever winds up as the backup may also have to contend with Townsend, a 12-year veteran, for playing time.

Bethea is coming off his second Pro Bowl season and just signed a $27 million contract, and former undrafted free agent Melvin Bullitt has established himself as a legitimate play-maker in Indy's secondary.

Coyer's job is devising ways to use Sanders and keep the big-hitting safety healthy. Sanders has started only eight regular-season games since being named the 2007 NFL defensive player of the year, but has practiced all week. It's the first time Sanders hasn't opened training camp on the physically unable to perform list since 2007.

"He's our leader back there, and you could say he's the most battle-tested Peyton Manning guy in the secondary," Hayden said. "He doesn't do a lot of talking, but when he leads, he leads by example and we need that."

The secondary isn't the only area making adjustments.

Indy's booked end pass rushers, Freeney and Mathis, both went to the Pro Bowl the last two seasons, rank first and second in sacks in franchise history and are No. 1 and No. 2 among all NFL players in forced fumbles since 2002.

If healthy, they won't lose any playing time.

But after taking another speedy pass rusher, Jerry Hughes, in the first round of this year's draft, the Colts are working on some new options.

Coach Jim Caldwell has said the Colts are experimenting with packages that would put all three on the field together. One possibility would make Hughes a standing rusher, a role the departed Raheem Brock played last season. Or Hughes could line up as a 3-4 linebacker, allowing the Colts to dial up more blitzes. Some teams actually projected Hughes as a linebacker.

Who wants to be called that? But it certainly fits for Indianapolis Colts safety Bob Sanders, who has missed more games in his career than he has started, a variety of injuries limiting the 2007 NFL Defensive Player of the Year for most of his six years in the league.

 You know things are bad on the injury front when a summer report hit NFL.com that said Sanders might be forced to retire, which was big news to Sanders.

"That was like something from the tabloids," Sanders said. "It was all laughable. It was kind of funny. I just shrugged it off and kept going."

That report sure looked erroneous Monday when Sanders took part in the Colts' first practice of training camp. For Sanders, getting out on the field for the first day of camp was something he hasn't done since 2007, making the reports of his demise all the more wrong. Sanders had opened on the PUP (physically unable to perform) list three of the past four years.

The truth is, Sanders said he barely paid attention to the report, but said he got calls from friends, family and teammates wondering if it was true, all with the same question: Was his career really over after six years?

"You can come up with any type of stuff, speculation about how guys are doing," Sanders said. "The only thing that is important is that I was here today and I'm ready. I'm as healthy as I've been in a long time. It's kind of weird they said my career was over."

When Bob Sanders has been on the field during his six seasons, he has been one of the best safeties in the NFL, and some say the heart of the Indianapolis defense. But it's hard to make plays from outside the lines.

That has led him to become the new "but" man on the Colts roster. Peyton Manning used to be that guy, but he won a Super Bowl to erase that.