"Dallas Clark earned first-team all-pro honors this season, heralding him as the best tight end in the NFL.He's surpassed many of the marks of Baltimore legend and Hall of Famer John Mackey in the Indianapolis Colts record book. And the New Orleans Saints defenders are quite aware they'll have to contend with him Sunday.

Yet it's almost certain that Clark would not be enjoying his current success if he'd listened to his heart instead of his coaches.

"I walked on at Iowa as a linebacker, and I just had it in my mind that I was going to try to be as good a linebacker as I could be," Clark says. "Then Coach (Kirk) Ferentz saw something in me and he wanted to try me at tight end. After about a year, I decided to try it."

After finally relenting, Clark transitioned so effectively that he won the Mackey Award as the country's top tight end as a junior in 2002 and became a first-round pick of the Colts the next spring.

So what was it that necessitated the fateful switch?

"He was very athletic. ... He worked hard, seemed to be very eager to please you," Ferentz says. "(But) when we went on the field, the things we saw (off the field), quite frankly, didn't translate into production as a defensive player.

"Sometimes, the abilities players have don't always translate when they are in the wrong position, and, clearly, we had him in the wrong spot."

But now Clark makes a living putting NFL defenses in tough spots. His value was on full display during the Colts' 2006 Super Bowl run, when he essentially replaced injured slot receiver Brandon Stokley. At 6-3, 252 pounds, Clark overpowered defensive backs, but he was much too quick and athletic for linebackers.

"He just loves playing," Ferentz says. "(Colts President) Bill Polian put it best when he said Dallas enjoys getting his ankles taped. That's the kind of guy he is."

Clark has played better than ever the past two seasons.

He had a big season in 2008, catching 77 passes for 848 yards, eclipsing the best years of Mackey, who helped revolutionize the position in the 1960s.

"Just hearing about what he's done," Clark says, "it's a true honor to be passing some of his records.

"I really don't believe it myself sometimes. That guy has done so much for this position and the NFL, and he's given so much. He's what this game is about.""