No timetable for Prince Amukamara

New York Giants cornerback Prince Amukamara has a moderate high ankle sprain.

But it's safe to say the level of Tom Coughlin's concern about the state of his cornerbacks as a whole is much higher than moderate.

Coughlin did not give a timetable for Amukamara's return, but the Giants' coach understands it could be several weeks before last year's first-round pick returns as the starting cornerback.

Amukamara was starting in place of Terrell Thomas, who reaggravated his surgically repaired right ACL early in training camp and has been out indefinitely. Coughlin also revealed that promising second-year defensive tackle Marvin Austin has suffered a setback with a back injury.

"I don't know," Coughlin said when asked about when Amukamara might be able to return. "These things are unfortunately longer than you would like them to be.

"If I were to say two or three weeks, I'd be guessing. These things do take time."

With Amukamara potentially missing a month or more, the Giants likely will go into the season opener against Dallas on Sept. 5 without two of their top three cornerbacks.

Thomas wrote on his website that his goal still is to play in the season opener.

"It feels strong and no swelling," said Thomas, who was able to avoid a third surgery on his knee. "I am getting back to my old self; my goal is to still play in the season opener.

"Rest is what is best for my knee. All the signs are showing of my return coming back with a strong and healthy knee are all positive."

However, when asked if Thomas potentially could be ready for the Cowboys, Coughlin didn't seem as optimistic.

"Not according to what I am reading, no," Coughlin said. "But I think you have to always give way to hope."

Coughlin has to hope the health of his team improves before the season opener. Starting left tackle Will Beatty has shown improvement with his back and could begin doing some individual work this week.

Also, impressive rookie cornerback Jayron Hosley might be able to shed his protective walking boot for his turf toe in the next few days and begin some light work.

The Giants need Hosley back in their secondary. Coughlin said the Giants will scan the free agent market for cornerbacks but help likely will have to come from within.

Veteran corners Michael Coe, Justin Tryon and Bruce Johnson all have an opportunity to compete for Amukamara's starting spot now.

Coughlin said he would like to keep Antrel Rolle and his safeties at their normal positions as opposed to having them help at cornerback.

"A lot of what has to happen has got to come from the inside here," Coughlin said. "I don't have any idea why these things continue to happen at that position but they certainly have for the last couple of years for us.

"We started with a lot of numbers and those numbers have dwindled now," he added of his cornerbacks. "We are certainly concerned. Concerned is a very modest word."