Phil Richards

Indianapolis

There is no scarcity of candidates to start at center when the Indianapolis Colts open the season Sunday at Denver. Where the shortage lies is in healthy limbs and digits, not to mention starter's credentials.

"All hands on deck," Colts coach Chuck Pagano said Monday.

Khaled Holmes is the starter designee, but he hasn't engaged in a full practice since suffering a high ankle sprain Aug. 7 during the Colts' preseason opener. Holmes' regular-season NFL experience consists of 12 snaps as a rookie last season.

Jonotthan Harrison took most of the preseason work at center, but he is an undrafted rookie who has been sidelined since Aug. 23 and his injury is of a most inimical nature at a position where snapping the football is job one. Harrison has a sprained right thumb.

Jack Mewhort is the Colts' rookie second-round draft choice and another possibility, not that he isn't otherwise occupied. Mewhort is scheduled to start at left guard. He also is the primary backup at left and right tackle with Xavier Nixon and Joe Reitz out with injuries.

If you're putting your money on who will start at center Sunday, put it on A.Q. Shipley, difficulties be darned.

Shipley was cut by the Baltimore Ravens on Saturday morning, signed by the Colts on Sunday, aboard the first thing flying that evening and at Colts complex before 7 a.m. Monday morning. He huddled with line coach Joe Gilbert for a crash course on the playbook and team terminology. By 10, Shipley was on the field with the first-team offense.

At least he's a specialist in crisis management, and the Colts are clearly in crisis.

Shipley spent 2009 on the Pittsburgh Steelers' practice squad, 2010 on the Philadelphia Eagles' practice squad and 2011 on the street. By 2012, he was with the Colts, but three games into the season, he had appeared in a single NFL game, that on special teams. He was a center without a professional snap on his resume.

Then he made 96 of them against the Green Bay Packers. He also made all the line calls against the Packers' complex, frequently blitzing front. He played a crucial, if anonymous, role in a memorable 30-27 comeback victory, the team's first game after Pagano was hospitalized to undergo cancer treatment.

"If you remember correctly, the week before that Green Bay game I was on the (Colts') practice squad," Shipley said. "They called me in that Monday and said, 'Hey, we're activating you.

" 'And, by the way, you're starting.' "

That's why Shipley's approach has never wavered: Prepare like you're a starter, because any Sunday you might be.

The Colts have changed their offensive coordinator, system and language since they traded Shipley to Baltimore in early 2013, but he is a quick study.

"A.Q. is a very, very bright guy," Pagano said. "Going through (the morning walkthrough) today, taking every snap with the first group out there he was pretty much flawless. It's not easy but we can help him on our end, and again, he's a bright guy and a lot of recall there."

Holmes said Monday that he is feeling better, "feeling good," and that he hopes to be a full practice participant Wednesday.

Even if that happens, there is no guarantee his ankle will react well, and if it does, starting four days later would remain a daunting assignment. Holmes is not in "football shape," and the game will be played in the thin Denver air at mile-high altitude.

Moving Mewhort to center would compromise two positions. Mewhort hasn't played center in a regular-season game since he was a high school senior at St. John's Jesuit in Toledo, Ohio, in 2009. He has worked little at the position this preseason and his backup at left guard hasn't played a regular-season snap at any position since 2012.

Lance Louis suffered a torn anterior cruciate ligament that season. He didn't play in 2013 after undergoing reconstructive knee surgery.

Shipley was a capable fill-in while starting five games at center for the Colts in 2012. He made nine starts as an injury replacement at guard for the Ravens last season.

Because the Colts center, whomever he is, will make the line calls against a front whose principals include Pro Bowl outside linebackers DeMarcus Ware and Von Miller while playing head-up on Terrance Knighton, the Broncos' very competent nose tackle, experience would be a boon.

Shipley is the only candidate who has any.

"We'll see as far as the health and availability of Khaled on Wednesday, and Jon Harrison, we'll see what that is," Pagano said. "Then we'll make our decision."

Email Star reporter Phil Richards at phil.richards@indystar.com and follow him on Twitter: @philrichards6.