NASHVILLE, Tenn. -- Forget about death and taxes.

When it comes to the Indianapolis Colts, at least, it seems there are but these two certainties in life: Peyton Manning will throw for 4,000 yards, Edgerrin James will rush for 1,400 yards and wide receiver Marvin Harrison will score 10 to 12 touchdowns. And, oh, yeah, the defensive players will be the convenient whipping boys when Indianapolis fails again to advance beyond the first round of the playoffs.

That might seem like an oversimplification to explain why one of the NFL's most talented teams tends to spit the bit every time the calendar flips over to January and the Super Bowl tournament commences. But in the NFL, as in life, perception almost always becomes reality. And, make no mistake about it, the Indianapolis defense could have the acerbic Ann Robinson as its pin-up girl, particularly given the results of the past three seasons.

	“	We all know what people are saying, believe me, that the defense keeps holding this team back. ... the only way to silence the (critics) is to get better, and we're going to do that. ”
		— Jeff Burris, Colts cornerback

You are the weakest link. Good-bye!

"We all know what people are saying, believe me, that the defense keeps holding this team back," said cornerback Jeff Burris, during a break here in combined workouts with the Tennessee Titans. "You don't want to pay attention to it, but you're aware, you hear the talk. I think it's unfair, but the only way to silence the (critics) is to get better, and we're going to do that."

It is an annual rite of summer for the Colts, this verbiage about defensive improvement, the talk of how the unit will do its share to reduce the odds of another playoff pratfall. So far, however, all the rhetoric has failed to produce results. In the three years of the Manning Era, the Indianapolis offense has never ranked statistically lower than No. 12 in the league and twice finished among the NFL's top 10 units. Conversely, the defense has never rated higher than 15th and twice has been in the 20s, including a No. 29 status in 1998.

And those defensive shortcomings extend beyond just pure statistics alone, with some infamous meltdowns in key games. This is a defense, remember, that surrendered 209 rushing yards to Lamar Smith -- never to be confused with Emmitt Smith -- in a first-round playoff loss to Miami last season.

Mostly it is a defense that, even a month before the start of the 2001 regular season, already is under the microscope. It's doubtful that the West Nile Virus is being so heavily scrutinized this summer. During its practices here with the Titans, the Indianapolis defense was like a pack of laboratory mice, with every missed tackle or busted coverage tediously dissected.

Some of the Colts defenders are privately irked by the criticism. But most veterans member of the unit acknowledged that, while the spotlight will always shine brightest on the "Big Three" stars of the offense, the true heat will be on the defense. And if they exit stage left again in the playoffs, a victim of another early-round defeat, it's a no-brainer where the blame will fall.

"Whether we agree or not, the simple fact of the matter is, we have to get better," strong safety Chad Cota said. "You can say you don't feel the pressure, but it's there."

General manager Bill Polian, never a big player in free agency, made few offseason moves to upgrade a defense that finished 21st in the league in 2000. The Colts signed tackle Christian Peter, a starter with the New York Giants, and journeyman linebacker Mike Morton. They brought back veteran Dwight Hollier, their starting middle linebacker last season. But if Indianapolis is to make legitimate improvement this season, it will probably have to come from some young veterans now cast in starting roles and from a few rookies.

The linebacker group will feature two new starters in second-year veterans Rob Morris (middle) and Marcus Washington (strongside), joining third-year pro Mike Peterson, one of the emerging young weakside players in the league. Washington played primarily as a "nickel" pass rusher in 2000 and Morris, the club's first-round pick a year ago, saw his season truncated by a quadriceps injury after only seven games.

	“	I feel like the job is mine now, even if I can't take it for granted, and I feel like I'm ready to be the player they thought I was when they brought me in here. ”
		— Rob Morris, Colts middle linebacker

The consensus is that the athletic Washington is a player, a youngster who could evolve over the next few seasons, into a terrific combination blitz/cover guy. But the jury is still out on Morris, a wild-man run-stuffer during his collegiate days at Brigham Young, and a player who now must find a way to ward off blockers while playing behind one of the NFL's smallest defensive fronts.

Recently married, Morris has toned down his act, and isn't jumping off bridges or trying to vault over cars anymore. That doesn't mean there aren't a few hurdles he has to negotiate to become a viable starter.

"Even though I didn't play much last year, I still feel like I learned enough of the ropes to be a lot more comfortable in camp this time around," he said. "I feel like the job is mine now, even if I can't take it for granted, and I feel like I'm ready to be the player they thought I was when they brought me in here. Physically, I feel great, and mentally I'm getting there. We have a lot of new guys stepping into the lineup this year, me included, and we all need to ratchet it up more."

In fact, the Colts figure to have at least five new starters, not an altogether bad thing given the results of the past few years. The abrupt retirement of end Shawn King, who was coming back from a year-long drug suspension but tested positive again this summer and decided he'd better walk away from the game, takes away one potential pass-rusher. The team is hopeful third-year defensive end Brad Scioli, who posted two sacks in 2000, can become a consistent rushman.

The secondary will have a new look, with David Macklin and Mustafah Muhammad vying for the starting job opposite Burris, and rookie Idrees Bashir already penciled in at free safety to replace Jason Belser, a nine-year starter the Colts opted not to re-sign. A second-round choice, Bashir will add some more range to the secondary, but will also make his share of rookie mistakes. He easily passes the eyeball test, a long and lean interior player who isn't a big hitter but does move well to the ball despite just 4.55 speed.

Well-spoken and acutely aware of his surroundings, it hasn't taken Bashir very long at all to realize the plight of the Indianapolis defense. He might be wet behind the ears, but Bashir is wise beyond his years, as well.

"The people all talk about how our defense has to get better and, to tell you the truth, we all talk about it, too," Bashir said. "We know we're the ones behind the eight-ball."

Len Pasquarelli is a senior NFL writer for ESPN.com.