NFL

Despite Austin’s optimism, Giants coach still worried

What was once a strength of the Giants — depth along their defensive line — is quickly becoming a weakness.

Coach Tom Coughlin admitted as much yesterday when he contradicted defensive tackle Marvin Austin’s upbeat assessment earlier in the day of the condition of Austin’s lower back, refusing to rule out structural damage.

And Austin was just the latest Big Blue defensive lineman to fall this week, a sudden crisis that claimed Shaun Rogers, Martin Parker and Justin Trattou and forced the Giants to sign ex-Broncos tackle Marcus Thomas after a quick tryout yesterday. Parker and Trattou were released yesterday.

Luckily for the reigning world champions, they still have Jason Pierre-Paul, Osi Umenyiora and Justin Tuck to anchor what was the NFL’s most dominant defensive line last year. But that line’s once-imposing depth is now starting to look like a baby pool.

The Giants lost Rogers (blood clot) for the season and also are expected to be without defensive tackle Chris Canty for the rest of the exhibition season and perhaps early in the regular season, and now Austin — the team’s second-round pick a year ago — has become a huge question mark again.

“A lot of the early symptoms were no longer there, but they’re going to do another set of tests on him, and we’re hoping that within a reasonable amount of time he can come back and play,” Coughlin said yesterday after the Giants’ first practice at the Meadowlandsafter departing Albany.

Asked if there is something structurally wrong with Austin’s back and not just tissue-related, Coughlin said: “They’re dealing with some issues there, but I can’t tell you exactly what it was.”

Coughlin’s dour read on the situation was surprising, considering Austin had given a much more positive assessment earlier in the day.

“It was just a little backache,” Austin said after getting tests at the Hospital for Special Surgery in Manhattan. “I don’t think it’s going to be something that lags on and on.”

Austin thought the pain could have stemmed from playing last Friday in the Giants’ 32-31 preseason loss at Jacksonville — his first appearance in a game since December 2009 due to various injury and off-the-field woes in college.

“Having not been out there for a while, my body is adapting to it,” said Austin, who showed flashes against the Jaguars of the dominance at North Carolina that made him a high pick. “It could have had a little effect, but I don’t think it was the whole reason.”

Nor could it be blamed on the infamous beds in Albany that several teammates are faulting for their own back problems.

“I don’t think it was the mattress’ fault. It was just an accumulation of things,” Austin said. “I didn’t have the best bed, but it wasn’t the worst, either.”

Whatever the reason, Austin’s back and the rest of the medical problems dogging his defensive line left Coughlin in a sour mood yesterday when that topic was broached.

The Giants tried to stem the tide by signing Thomas, a 6-foot-3, 307-pound tackle who had been out of work after turning down what he considered a low-ball offer to return to Denver following 11 starts last season, to a one-year deal. Bobby Skinner, a defensive lineman who had been with the team just one practice, was waived to make room for Thomas.

Thomas got a one-year deal from the Giants, who could definitely use him to be the reliable — if not prolific — presence he was in five seasons with the Broncos. “We feel good [about the defensive line] except for the fact that at the tackle position, where we thought we were deep, we’re all of a sudden not,” Coughlin said. “I can’t feel very good about that when I really did think we had a lot of people who could play and we would be good in that spot.”