It's not all on Andrew Luck

ANDERSON, Ind. -- The Colts' 2012 season was magical.

Head coach Chuck Pagano won a battle against cancer. Interim coach Bruce Arians earned coach of the year honors. Andrew Luck lived up to his billing as one of the best quarterbacks to enter the NFL in decades.

So often, though, magical playoff teams turn into one-year wonders. There's a sudden drop-off the next year. Wisely, the Colts built on their success. General manager Ryan Grigson attacked unrestricted free agency with $134 million worth of contracts. Arians left for the Arizona Cardinals, so Pagano brought Pep Hamilton from Stanford to be the offensive coordinator. Hamilton is making the offense a moving target, switching more to the run.

As long as Luck is their quarterback, the Colts know they have a horseshoe of good fortune on the side of their helmets.

Here are the five things I learned at Colts training camp.

1. Position battles: Once Ahmad Bradshaw is cleared to practice, there will be a great battle for playing time at running back. Vick Ballard, a tough runner with decent hands, is the first-team RB since Bradshaw is on the physically unable to perform list. That doesn't prevent Bradshaw from getting healthy and becoming the starter. Also in the mix is former first-rounder Donald Brown, but he could end up as the No. 3 back. Mike McGlynn is the starting right guard, but don't be surprised if third-round choice Hugh Thornton makes a run at the job. At 334 pounds, Thornton is a bigger body on a line that is trying to become more physically imposing. On defense, there is plenty of competition. Josh Chapman and Aubrayo Franklin are wrestling for the starting nose tackle job. One of the inside linebacker slots is open; Kavell Conner and Kelvin Sheppard will be in a three-way competition once Pat Angerer is healthy. Angerer is recovering from two foot operations and is waiting to be cleared to practice. Once he is, the competition for the inside linebacker spot next to Jerrell Freeman will be one of the best battles in camp. Cornerback, once a weakness, is becoming a strength. Vontae Davis and Greg Toler are the starters, leaving a good battle for the No. 3 spot. Cassius Vaughn and Darius Butler did a lot of good things for the Colts last year, and both are vying to be the No. 3 corner.

2. A new Pep in the step on offense: So much of the Colts' success last year was Luck. Without much of a running attack, Luck was asked to carry the offense. He threw 627 passes, but nothing was easy. Because Arians called more 10-plus-yard and more 20-plus-yard throws than any other coordinator in football, Luck completed only 54 percent of his passes and was sacked 41 times. No more. Hamilton, the team's new offensive coordinator, is changing the culture of the offense. Instead of being a three-receiver offense, the Colts will feature their two tight ends: Coby Fleener and Dwayne Allen. The Colts used two-tight end sets on 368 plays last year. It's not out of the question for the Colts to look more like the San Francisco 49ers' offense than the old Colts. Heck, for the first time in years the Colts have a fullback, and Hamilton plans to use him. Here's the philosophy: At Stanford, Luck, Jim Harbaugh and Hamilton stressed the physical approach to offense. While college coaches such as Chip Kelly and Doug Marrone prefer to use a fast-tempo offense to tire the defense, Hamilton and the old Stanford staff stressed wearing down defenses physically. The Colts won 11 games last year, but Luck had to pull out seven fourth-quarter comebacks to make that happen. With Aaron Hernandez out in New England and Dennis Pitta out in Baltimore, the Colts might have the best tight end duo in Fleener and Allen. Hamilton plans to use that strength and treat games like a heavyweight fight.

3. Has Darrius Heyward-Bey found a home? Heyward-Bey was a disappointment in Oakland. Al Davis made Heyward-Bey the seventh pick in the 2009 draft, and he clearly was a disappointment. Hands were the problem. Heyward-Bey started 25 games in his first two years and had only 35 catches. In Indianapolis, Heyward-Bey hopes to get his career kick-started, and this could be a good fit. Reggie Wayne raves about his new teammate's skills. Wayne wishes he had Heyward-Bey's size and speed. Wayne has been one of the league's most dependable receivers for a long time, but he knows Heyward-Bay creates plenty of matchup problems. Heyward-Bey could do for Indianapolis what Jacoby Jones did for the Baltimore Ravens late in their Super Bowl run. Jones' speed and the threat of going deep opened up the middle of the field for Anquan Boldin and the team's two tight ends. Heyward-Bey cost the Colts only $2.5 million. It could be a bargain. In the meantime, T.Y. Hilton, last year's third-round pick, looks confident running his routes and will also challenge for playing time. The Wayne-DHB-Hilton three-receiver threat is pretty formidable.

4. Turning the corner at corner: Ryan Grigson's best work as GM might have been at cornerback. A year ago at this time, the cornerback position was a turnstile for the Colts. Whether it was street free agents, trades or waiver claims, Grigson was in a desperate search for coverage players. Most of his acquisitions from last summer are gone, but now the Colts are at least five deep at cornerback. Last year's trade for Vontae Davis and the free-agent acquisition of Toler give Grigson two starters who can cover. From the roster churning at corner last year, the Colts have brought back Vaughn, Butler and Josh Gordy. A weakness has turned into a strength, but overall, the secondary is so much better than when Grigson started. Safety Antoine Bethea has always been solid, but the Colts added a physical presence at safety with the signing of LaRon Landry.

5. Adding girth to the 3-4 defense: To fit Pagano's 3-4 scheme, the Colts took numerous gambles on players last year. Grigson tried to patch spots by getting some players he knew from his personnel days in Philadelphia as well as some players Pagano knew from his days as an assistant at Baltimore. This year's mission was to anchor the front seven with bigger, more physical players. The Colts gave up 2,200 rushing yards last year and a 5.1-yard average. The Colts will tackle that problem with mass. The Colts signed San Francisco 49ers nose tackle Ricky Jean Francois, but the Colts have enough size that they could put him at left end. He's 297 pounds. At nose tackle, the Colts can alternate the 320-pound Franklin and the 341-pound Chapman, a fifth-round pick from last year who was injured in 2012. The Colts also brought in former Green Bay Packer Erik Walden at outside linebacker. If the Colts are going to make a successful second run at the playoffs, they need to be better at stopping the run.