Thomas (quadriceps), who re-injured his quadriceps on Wednesday, is slated to go on injured reserve, the Indianapolis Star reports.

Thomas went down with a quadriceps injury two games into last season and subsequently missed the Colts' remaining contests. Although he reported feeling fully healthy entering camp, Thomas unfortunately fell victim to the same injury that cost him the better part of last season. With Thomas going down, second round pick Jack Mewhort's seems destined to start at left guard, with Lance Louis likely becoming his back-up.

Colts LG Donald Thomas re-tore his quad during Wednesday's practice and will need surgery.

It's the same injury that cost Thomas the final 14 games of last season. This tear will likely cost him all 16 games this year, meaning he will have played in two games since signing a four-year, $14 million deal with the Colts in March of 2013. It's another stinging blow to the Colts as Thomas was projected to both start at left guard and be the primary backup center. They'll now have to thrust second-round rookie Jack Mewhort into a major role.

Thomas appeared to re-injure his right quad at practice Wednesday, the Indianapolis Star reports.

With Thomas, who has been working as the starter at left guard for the Colts, now banged up, Jack Mewhort and Lance Louis figure to see added practice reps.

A source tells the Indianapolis Star's Stephen Holder Colts LG Donald Thomas re-injured his quad during practice Wednesday.

Thomas missed the final 14 games of 2013 with tears to both his quad and bicep. He is headed for an MRI. Rookie Jack Mewhort stepped in at left guard after Thomas went down, and would likely man the position if Thomas is force to miss any time.

Colts LG Donald Thomas (quad) is not participating in OTAs.

This doesn't come as a surprise. Thomas missed the final 14 games of last season and is still rehabbing the injury. He's expected to be ready for the start of training camp. Lance Louis has been running with the first-team offense at left guard in OTAs, while second-rounder Jack Mewhort works with the twos.

Colts GM Ryan Grigson revealed that, in addition to his torn quad, LG Donald Thomas tore his biceps in Week 2.

The injuries remarkably happened on the same series against the Dolphins. Thomas was playing through the torn biceps but later tore his quad. Thomas is still working his way back but should be ready for the start of training camp. He'll slide right back into his starting spot next to LT Anthony Castonzo.

Colts LG Donald Thomas needs season-ending surgery on his torn quadriceps tendon.

It's a big blow to the Colts. Signed to a four-year, $14 million deal in March, Thomas was a solid and versatile interior performer. The Colts will be forced to turn to third-round rookie Hugh Thornton, who primarily worked at right guard during the preseason.

Profootballtalk.com reports Colts LG Donald Thomas tore his quadriceps in Week 2 against the Dolphins.

Colts LG Donald Thomas was carted off the field Sunday with an injured right knee and will not return.

He was replaced by rookie Hugh Thornton. Thomas was quickly declared done for the day, which bodes poorly for his chances of returning anytime soon. The Colts signed Thomas to a four-year, $14 million contract during the offseason.

Coach Chuck Pagano confirmed the Colts will play Donald Thomas at left guard.

Thomas, who signed a four-year, $14 million contract, has played all three interior line positions. The Colts believe he's an equally strong pass protector as run blocker. If the season started today, Indy's O-Line would look like this: LT Anthony Castonzo, LG Thomas, C Samson Satele, RG Mike McGlynn, and RT Gosder Cherilus. They could afford to upgrade on McGlynn at right guard.

Colts agreed to terms with OG Donald Thomas, formally of the Patriots.

Indianapolis made it a priority to upgrade the offensive line, and they have added RT Gosder Cherilus and now Thomas to come in and help solidify things. Thomas started seven games for the Patriots last season and proved to be a top reserve. He can play any of the interior line positions, and the Colts need help at all three.

The Boston Globe reports the Patriots have interest in re-signing free agent G/C Donald Thomas, but it's "fully expected" he'll test the open market.

Thomas was an invaluable reserve behind Logan Mankins and Dan Connolly last season, but his strong play may have priced him out of the Patriots' plans. The former sixth-round pick won't turn 28 until September.

ESPN Boston believes free agent G/C Donald Thomas has proven he's capable of being a starter.

Thomas ended up playing 616 snaps last season thanks to injuries to Logan Mankins and Dan Connolly, and graded out as a top-20 guard in Pro Football Focus' ratings. With Mankins and Connolly both signed through 2014, there's a pretty good chance the Pats will lose Thomas to free agency. Going on 28, Thomas should draw multi-year offers.

Patriots G/C Donald Thomas has stood out in training camp.

It's worth noting because Thomas appeared buried on the offensive line depth chart and was given a 30 percent chance of making the 53-man roster by ESPN Boston earlier this month. He's still on the bubble, but saw first-time reps on Tuesday and appears to have an edge on Robert Gallery for a roster spot.

ESPN Boston gives G/C Donald Thomas a 30 percent chance of making the Patriots' 53-man roster.

Thomas made one start as an injury replacement last season, but the team is deep on the interior line. Projected starting guards Logan Mankins (ACL surgery) and Brian Waters (personal) are questionable for training camp, but the 26-year-old will have plenty of competition, including Ryan Wendell, Nick McDonald, and Jamey Richard.

Patriots re-signed OL Donald Thomas.

Thomas is back as insurance on the line thanks to left tackle Matt Light's ankle injury.

Patriots signed OG Donald Thomas.

Thomas brings starting experience from his time with the Dolphins. He'll provide depth with G Dan Connelly moving to center thanks to Dan Koppen's left ankle injury.

Lions waived OG Donald Thomas.

A 12-game starter with the Dolphins in 2009, Thomas was out of the league for much of last season.

Lions signed OG Donald Thomas.

Thomas started 12 games with the Dolphins last year, but he's been out of the league since the start of the 2010 season. He'll add depth inside with RG Stephen Peterman nursing a foot injury.

Eagles worked out free agent OG Donald Thomas on Tuesday.

The Eagles are the third team to give the former starter a tryout since his offseason release from the Dolphins. Philadelphia has had issues at RG all season, and Thomas would provide experienced depth.