Offseason workouts are already in full swing for Indianapolis quarterback Andrew Luck.
Colts left tackle Anthony Castonzo said Tuesday night that Luck is training at team headquarters roughly seven weeks before the start of the team's OTA program. Focusing on the 2016 campaign is helping Luck close the door on last season after he missed the final seven games with a lacerated kidney.
"He's extremely optimistic about the whole thing, as is his nature, and is just working tirelessly to try and get back," Castonzo told co-host Gil Brandt and me on SiriusXM NFL Radio. "It just didn't end up working out last season because it was a really serious injury. But I've seen him quite a bit at the facility working out.
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"He's able to get his offseason started early because he didn't have the wear-and-tear from the last half of the season so he's good to go. He's making the most of the fact that he didn't have to play those last games. As bad as it is, he's finding a silver lining. That's his personality -- moving forward and being the best he can be."
Castonzo is looking forward to learning what type of system offensive coordinator Rob Chudzinski will be installing now that he was named to the position after serving as an interim replacement following last November's firing of Pep Hamilton.
"We didn't see a big difference but (Chudzinski) couldn't come in and change the entire offense at midseason because it would have been a disaster," Castonzo said. "We kind of saw a little bit. We went to a little more zone schemes to run the ball. The other thing was that we didn't have Andrew.
"So what it's going to be like? I wish I could tell you. I don't know but I'm excited to find out."
One thing Castonzo does know: The Colts must improve from last season's 8-8 mark to regain their status as AFC South kingpins after a two-year run as division champion was ended by the Houston Texans.
"A lot of things went wrong," Castonzo said about the 2015 season. "Some plays just went the wrong way. But we didn't play to our potential is what it really came down to. We have guys on our team that can get the job done. We just didn't play our best football. We need to play to our potential. As long as we do that, we'll be just fine."
A healthy and productive Luck wouldn't hurt either.