For someone who already had accomplished so much in such a short period of time, Andrew Luck found himself in unexplored territory this afternoon.

So, that’s what OTAs are all about.

“I missed these last year,” the Indianapolis Colts’ second-year quarterback said after today’s organized team activity session.

It was the third of 10 OTA workouts that are spread over four weeks and culminate with the team’s three-day mandatory minicamp June 11-13. The June 12 session is at Lucas Oil Stadium and open to the public at no charge.

Luck is coming off a decorated rookie season: Pro Bowl selection, playoff berth, a club rookie-record 11 wins, a variety of league and club passing records.

But the No. 1 overall pick in the 2012 draft was limited in his preparation for what was to come. He participated in a three-day rookie minicamp and three-day mandatory minicamp, but academic requirements at Stanford forced him to miss other OTAs, when on-field work accelerates and includes 11-on-11 drills.

Now, Luck is taking full advantage.

“It’s great to get out on the field with the defense and troubleshoot some stuff,” he said. “All of us haven’t run this offense; I ran some of this stuff at Stanford.”

First-year coordinator Pep Hamilton is installing an offense that figures to be different from Bruce Arians’ approach last season. It’s expected to focus on a power running game and a shorter, more rhythmic passing game.

Luck had his ups and downs during 11-on-11 work. He hit T.Y. Hilton for a couple of touchdowns in red-zone work, but also was intercepted by linebacker Kelvin Sheppard,whomade a nice break in front of a receiver.

“It stinks when you throw interceptions in the red zone. I’m not happy about that,” Luck said. “But the silver lining is it’s our defense and hopefully we’ll get some of those during the season.”