INDIANAPOLIS — The Indianapolis Colts are finally getting bigger on the defensive line, and it's all by design.

For years, coaches said they preferred speed to brawn, but last year's struggles against the run prompted the Colts to tweak their philosophy during last week's NFL draft.

They took 303-pound defensive tackle Fili Moala of USC in the second round and 319-pound defensive tackle Terrance Taylor of Michigan in the fourth round, giving them a potentially big one-two punch in the middle of the defense. All Moala and Taylor have to do now is prove they can hold up against the bigger, stronger offensive linemen in the NFL, and show new coach Jim Caldwell they can be difference-makers.

"With me, it's just a matter of spending more time with it, getting more flexible, paying more attention to my technique and executing the play calls," Moala said after Friday's rookie mini-camp. "You have to come out here and play against some of the best offensive linemen in the league, so you've got to prepare yourself physically and mentally."

The Colts have high expectations for Moala, who played both defensive end and defensive tackle in USC's 3-4 defense. He could play exclusively at tackle or he could rotate from tackle to end.

Indy had success with Raheem Brock playing that role before. Not surprisingly, Moala, albeit a little heavier, fits Brock's mold. Both are 6-foot-4, were all-conference choices in major conferences and weren't exactly sure what they'd play when they arrived in Indy.

The major difference: Brock is listed at 274, while Moala is nearly 30 pounds heavier and perhaps a better fit inside.

"I'm way more comfortable inside because it's fun and I like being in the grit," Moala said.

Taylor is a more traditional defensive tackle. He's listed at 6-foot, 319 pounds and lifted 225 pounds 37 times at the NFL combine in February — the most by a defensive lineman.

Together, the Colts may finally have the combination they've been searching for.

In 2005, they signed 300-pound defensive tackle Corey Simon, then traded for 300-pound Anthony McFarland in 2006 when Simon couldn't play. The two could have been paired together in 2007 to defend Indy's Super Bowl title, but after Simon spent most of 2006 on the non-football injury-illness list with polyarthritis, Indy released him in August 2007 and McFarland injured his knee in training camp.

Last year, the Colts thought they had another good match with 296-pound Ed Johnson and 299-pound Quinn Pitcock. But Pitcock retired after one NFL season and Johnson was released in September following his arrest on drug possession charges.

So the Colts used 254-pound Keyunta Dawson and 265-pound Eric Foster in the middle, and they wound up with one of the NFL's worst run defenses.

Moala and Taylor could change all that.

"We feel good about what we did, and we stayed within the parameters we set," team president Bill Polian said after the draft. "We didn't have to break the mold in any way except that we wanted to get bigger at defensive tackle, and we did that."

The Colts added help at other positions, too, and on Friday, the first day of the three-day mini-camp, Caldwell finally got a good look at his new players.

First-round pick Donald Brown didn't disappoint.

"It's hard to evaluate a guy on just one day, but let me just say, he did very well," Caldwell said of the running back from Connecticut.

Caldwell, who has been Peyton Manning's position coach the past seven seasons, also got a chance to work with Purdue quarterback Curtis Painter.

The Colts believe Painter has the size, arm strength and smarts to run their offense, though Painter is now cramming to learn the expansive playbook.

"It's pretty big," Painter said. "There are some similarities (to Purdue), which is good. But it's quite a bit thicker and a lot of work."

For Day 1, though, Caldwell liked what he saw.

"I've been extremely excited about having an opportunity to direct the squad and on the first day, you anticipate things are not going to go as smoothly as you'd like," he said. "But it went smoothly today."