The cram sessions could take all week.
While this isn't how the Colts envisioned opening the season Sunday at Denver, plugging in yet another potential new starter at center, injuries have left them with no choice.
''Going through today, taking every snap with the first group out there, he was pretty much flawless,'' coach Chuck Pagano said. ''It's not easy, but we can help him on our end.''
The Colts need all the help they can get.
Starting left guard Donald Thomas sustained a season-ending torn right quad during the first week of training camp. Starting center Khaled Holmes sprained his left ankle on the first possession of the preseason opener, hasn't practiced since, and Wednesday's long-anticipated return to practice is no sure thing, either
Seventh-round draft pick Ulrick John is expected to miss significant time with a lower right leg injury, though he has not been placed on injured reserve. Backup center Jonotthan Harrison has been out for about a week with a right thumb injury. Second-round pick Jack Mewhort, the projected replacement for Thomas at left guard, has been dealing with a sore right knee. And two of the Colts' most versatile backups, Xavier Nixon (knee) and Joe Reitz (ankle), also are out.
So when Shipley was waived by Baltimore on Saturday, general manager Ryan Grigson wasted no time putting in a claim.
Shipley, who made five starts with Indy in 2012, arrived in town Sunday evening, showed up at the complex early Monday morning and immediately was working with the starters.
''It's been an interesting weekend for sure. You go from a down, then you get an up. You find out you're coming here, then you're on a plane three hours later, and eight hours later you're back in here running reps,'' Shipley said. ''It's definitely a whirlwind, but that's part of our business. It's what we do and I wouldn't have it any other way.''
The good news is that Shipley has a relationship with Luck dating to Luck's rookie season. But if Shipley starts Sunday, it would be the fourth starting center the Colts have used in five games. That won't help with the continuity on an offensive line that has allowed 73 sacks and dozens more hits over the past two seasons.
Plus, the middle of the line might be one of the most untested in football.
Mewhort, a rookie who started at center in the Colts' preseason finale, will likely shift back to left guard Sunday. Second-year guard Hugh Thornton has moved from the left side to the right. Holmes took only 12 offensive snaps in his rookie season, Harrison is an undrafted rookie, and Shipley started nine games at guard last season in Baltimore.
None of that will make things easier against a Denver defense that spent more than $100 million to upgrade its pass rush and pass coverage
''It's a little different, especially when you're going through camp with other people and getting the chemistry down,'' Thornton said. ''But as an offensive line, as an offensive unit, I believe in the guys we have and that we'll be cohesive as a unit.''
The strangest sight Monday wasn't seeing Shipley working out with the starters, it was the folded chair inside Robert Mathis' locker.
The NFL's defending sacks champ began serving his four-game suspension for violating the NFL's performance-enhancing substance policy on Saturday. He will not be eligible for reinstatement or allowed in the team complex until after the Colts host Tennessee on Sept. 28.
So Mathis found another way to inspire his teammates.
He wrote the words ''Gone fishin''' on a small dry erase board in his locker and then placed a small note on a large black-and-white photo of himself to encourage his teammates to work hard until he gets back.
''When you finally reach that day that you can't play and you can only watch, then you will know how much you love something that you once took for granted,'' the note read in part.
It's a message that goes well beyond the defense, and right to the heart of the gang charged with protecting Luck on Sunday.
''It felt good to get back out there with Andrew, it's just getting down the calls now,'' Shipley said. ''I mean, terminology is terminology, and I'll get that down in the next day or two. Football is football.''
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