ALBANY, N.Y. -- Cornerback Terrell Thomas suffered an injury to his surgically repaired right ACL and likely will undergo an arthroscopic procedure to determine the extent of the injury, according to the New York Giants.
A source said it is believed that Thomas suffered a partial tear of his ACL, but more will be known after the arthroscopic procedure.
Thomas was sent to the Hospital for Special Surgery in Manhattan for an MRI on Monday after he experienced swelling in his knee, which he had surgery on last September after suffering the second torn right ACL of his career.
"Terrell re-injured his ACL," Ronnie Barnes, Giants senior vice president of medical services, said in a press release. "At this point, he will most likely undergo an arthroscopic procedure to determine the extent of the injury to the ACL."
"However, no decision has been made at this point," Barnes added. "Terrell is going to consult with Dr. (Arthur) Ting, who performed an allograft reconstruction of the ACL in September."
Thomas took a spill during Sunday's practice while covering Domenik Hixon and later sat out the final portion of practice while icing his knee.
The cornerback is attempting to return from a season-ending torn ACL injury suffered last preseason and had been cleared by doctors to practice without limitations. He first tore the same ACL at USC in 2005 but successfully returned from that setback.
Tom Coughlin was very worried and expressed concern for his starting cornerback prior to the Giants releasing the update on Thomas.
"He walked up to me after practice (on Sunday) and thought he felt good," Coughlin said earlier in the day. "He didn't really seem to have any issues and then this morning when he came back in, it was swollen."
The Giants also sent linebacker Michael Boley to the Hospital for Special Surgery to have his hamstring injury examined. Boley's injury isn't thought to be as serious.
Thomas is the Giants starting cornerback opposite Corey Webster. His return was to be a boost to the defending Super Bowl champion's defense.
If Thomas is out, Prince Amukamara, Michael Coe, Justin Tryon, Jayron Hosley and Bruce Johnson are among the candidates to replace him as a starter. Hosley suffered a laceration to his knee on a fall on Monday in camp and required stitches.
The Giants are no strangers to injuries decimating their secondary. Thomas was one of five cornerbacks who were placed on injured reserve last year with season-ending injuries. Thomas, Johnson, Coe, Tryon and Brian Witherspoon were lost for the season.
ACL injuries are nothing new to the Giants.
Thomas, Witherspoon, Hixon, linebacker Jonathan Goff, linebacker Clint Sintim, tight end Travis Beckum and tight end Jake Ballard all suffered torn ACL injuries last season. Hixon and Sintim are attempting comebacks after tearing ACLs in consecutive seasons.
Witherspoon attempted a comeback from a torn ACL this year but tore his ACL again in OTAs.
The Giants signed Thomas to a four-year, $28 million deal in free agency, but it is a low-risk, high-reward deal. He reportedly got a $1 million signing bonus and receives that amount if he is on the team this season. The team has a $6 million option on Thomas in March.
Thomas worked very hard to rehab his knee and be back to start camp. Now he will have to wait to see just how bad his latest knee injury is.