ST. LOUIS -- On draft day, Rams coach Mike Martz was so excited that defensive tackle Jimmy Kennedy was available that he did a dance at the podium.

But just like the team's other first-rounders on the defensive line in recent years, Kennedy has had to learn patience. The 12th overall pick was inactive the first two weeks and saw limited action on special teams last week.

On Sunday, he's likely to get his first chance to play his position. Improved showing in practices the last few weeks, combined with Ryan Pickett's left ankle and Achilles' tendon injuries, could give him a chance to play.

"He's learning what this is all about, and the intensity that's required," Martz said. "He's buying into how we practice, and the defensive line has done a terrific job of pulling him in and not letting him stay on the outside."

The 320-pound Kennedy is excited about finally getting an opportunity after mostly watching the first three games. He would have missed the second game anyway due to an infected elbow caused by a turf burn.

"I know my stuff," Kennedy said. "I'm still a rookie and I just hope I won't make any rookie mistakes.

"I'll go out there and give it everything I have."

Kennedy is one of four first-rounders on the defensive line, and none of them have gotten off to a scintillating start. That has helped him stay calm while waiting for his turn.

Grant Wistrom, the sixth overall pick in 1998, had zero starts his rookie season while playing in 13 games. Pickett had no starts in 2001, and Damione Lewis, taken on the 12th pick in '01, got three starts his rookie year.

Other defensive tackles picked in the first round this year are having similar growing pains.

"It's a tough position," Kennedy said. "You can't just beat your guy with speed, you've got to have strength and you have to be one of the smartest players on the field.

"It's tough to learn and it's real tough to dominate."

That said, Kennedy said it's been a frustrating start to his career.

"But I know my time will come," he said. "I'm young and I have to get the coaches to believe in me and have confidence I can go out there and get the job done."

Pickett has been nursing a high ankle sprain and developed Achilles' tendon pain while compensating for the other injury. He was in street clothes on Friday.

"It just has come over time, just running on it and playing on it," Pickett said Friday. "It felt pretty good today, but they held me out and said to wait until Sunday."