The only thing we really know about the injury to Giants cornerback Terrell Thomas’ surgically repaired right ACL is that he won’t be back on the field anytime soon.

“His knee is going to require some time,” coach Tom Coughlin said Wednesday.

The Giants aren’t in a rush to diagnose anything, which is why Thomas, who missed last season with a torn ACL and re-injured it at training camp Sunday, is out in California, seeking a second opinion with his doctor, Arthur Ting.

What we don’t know is the severity of the injury or how the team plans on dealing with the fallout. If the ACL graft is completely torn, it’s likely cornerbacks Prince Amukamara, Michael Coe, Justin Tryon, Jayron Hosley, Antwaun Molden and Dante Hughes would be competing for a starting spot opposite veteran Corey Webster. If it’s just a partial tear and the majority of the ACL graft is still in place, Thomas could return at some point this season.

“I’m always going to hope,” Coughlin said. “I have enough information, though, to counter some of that hope.”

Complicating matters for the Giants is Thomas’ presence in the nickel packages. As a physical corner who led the Giants in tackles in 2009 and 2010, Thomas was a perfect fit in the nickel, even if he started in the base package. The plan was for Thomas to resume that role this year, CB coach Peter Giunta said on Wednesday, with presumably Amukamara or Coe playing on the outside.

“Right now, we have [safety] Antrel Rolle playing that spot, and he did a great job for us all of last year,” Giunta said of the starting safety. “We have Jayron Hosley, we have Dante Hughes, we have Antwaun Molden, Corey will go inside and play a little bit in that spot. We’ll give the guys plenty of reps. During the preseason games, we’ll be able to adjust and use people the way we want to try to fill that role for us.”

Rolle’s history at cornerback and experience playing nickel in the Giants defense might belie his preference to remain at safety. When Rolle arrived at camp, he seemed proud to announce that the team has “a lot of guys up front, secondary wise, that can fill up every corner spot.”

“I think if it was up to ‘Trel, I think he likes being back there [at safety],” said Coe, who said he exclusively plays on the outside as opposed to nickelback. “But you just have to see who steps up in that role. Hughes is here. He played three years and started at nickel for the Chargers.”

Safeties coach Dave Merritt, however, said Rolle has been open to returning to nickelback before and after Thomas’ injury.

"Just two days ago, I had a one-on-one conversation with him [and said] ‘Antrel we’re going to put you down in the slot just like your position last year. I’m not saying its going to be permanent, but we need you to get some reps there,'" Merritt said. "He said, 'No problem, Coach. And then, of course, after the Terrell Thomas situation, I went back to him again. I said ‘O.K. Antrel, you need to think of yourself as a starter at that position.’ He said whatever it takes.”

If Rolle is willing to play nickel, then the team would likely need to re-sign veteran safety Deon Grant -- something general manager Jerry Reese previously said is a possibility. (As reported earlier, backup safety Tyler Sash will be suspended for games for a violation of the league’s performance-enhancing substance abuse policy.)

That leaves the question of who will play cornerback on the outside, which seems to be a three-way race between Amukamara, Coe and Tryon.

For Amukamara, now in his second season after an injury-plagued rookie campaign, Thomas’ injury is unfortunate but it doesn’t change a thing. The former first-round pick insists his “goal is still the same,” meaning he’s coming in to “compete for a starting spot. His competition will be Coe and Tryon. Like Amukamara, both of those players are each coming off injuries. Coe had a season-ending shoulder issue last year and Tryon, a midseason pickup, lasted only three games before being sidelined for the rest of the season with an arm injury.

Following Thomas’ injury, there's not a lot of good news to go around. Coughlin wants a medical explanation for why these ACL injuries keep repeating themselves and what the team can do to avoid the issue in the future. However, he doesn’t think Thomas was brought back too quickly. (It’s been nearly a year since he tore his ACL in the 2011 preseason.)

Coughlin was clearly distraught to be discussing more bad injury news with the press.

“[Thomas] did a great job of masking, I’m sure, his true emotions,” Coughlin said. “His emotions I am sure are very fragile at this point in time. He did not show that with me. From what I understand, with [Dr. Ronnie Barnes], he kept a stiff upper lip."

If the Giants suffer any more injuries at corner, Coughlin might be the one in danger of losing control of his emotions.

Follow the Giants and Alex Raskin on Twitter @CBSSportsNFLNYG and @alexraskinNYC.