Injuries to New England defensive players, such as safety James Sanders, left, yielding a touchdown reception to Seattle receiver John Carlson on Sunday, have forced the Patriots to rely on backups to plug holes in the defensive unit.

The Providence Journal / Bob Breidenbach

SANTA CLARA, Calif. — So now what?

The New England Patriots and coach Bill Belichick were rightfully relieved after pulling out a win on Sunday against the Seattle Seahawks, getting the first of four much-needed wins to finish the regular season against a Seahawks team that is tougher than its two-win record would attest.

But now what?

Ty Warren didn’t play Sunday, and his availability for the rest of the season is uncertain due to a partially torn groin.

The fulcrum of the Pats’ defense, Vince Wilfork, left the game after six snaps with a shoulder injury.

Linebacker Tedy Bruschi, already limited by a left knee problem the past couple of weeks, had further damage done to the joint in the first half and flew home to Boston to undergo tests yesterday.

Safety James Sanders also left the game after suffering a rib injury toward the end of the first half.

There was another scary second-quarter moment when Mike Vrabel was shaken up, but he missed just one play.

In place of the injured players stepped Junior Seau, Rosevelt Colvin, Le Kevin Smith, Mike Wright, Antwain Spann and Lewis Sanders, who lined up at safety and linebacker rather than his usual cornerback at times.

All of those subs performed well as New England held off the Seahawks for the come-from-behind victory.

“Thank goodness we had them,” coach Bill Belichick said of Smith and Wright, though he could have been talking about all of the fill-ins.

Though Seattle put up a valiant fight, it had folded late in several other games this season, and backup quarterback Seneca Wallace, who started in place of injured Matt Hasselbeck (back), isn’t Kurt Warner, who is putting up MVP-worthy numbers for an Arizona team that will be in Foxboro later this month.

While Belichick provided no update on the status of his injured players, saying they were being evaluated and he wouldn’t know more until tomorrow, Seau feels that New England can’t worry about who might and might not be on the field in the days and weeks ahead.

“Basically our mindset is to look at film today and take it one day at a time,” he said yesterday. “We’re not going to worry about injuries; it is what it is and the team that we put on the field will be able to focus on winning that game.”

Patriots players listed second or third on the depth chart are constantly told to be ready, because when their chance comes they’ll be asked to step in and perform. And when it’s one or two reserves who are called upon, it helps that there are veterans who can help take some of the pressure off and possibly cover up mistakes.

But how will the defense be affected if more than half of the players at any given time are inexperienced reserves?

There’s no denying the fact that New England needs to win all of its remaining games, and as of right now it’s looking as though the Patriots will have to win the AFC East to get into the playoffs, because Indianapolis and Baltimore, the two teams ahead of them in the wildcard race, hold tiebreaker advantages over them.

On its face, Sunday’s game in Oakland shouldn’t be that difficult — it appears that many of the Raiders have packed it in, content to collect their paychecks as the losses keep piling up.

The week after, however, is when the Cardinals come to Gillette Stadium. With it being in New England around Christmastime, there’s a strong possibility the weather conditions will favor the Patriots. But the Pats can’t count on an assist from Mother Nature, and will need to find a way to contain Arizona’s high-octane offense, led by Warner and receivers Anquan Boldin and Larry Fitzgerald.

If the front seven is in disarray and unable to put pressure on Warner, that leaves the secondary, which has been the weakness of the defense for much of the year, exposed against the Cards’ Pro Bowl wideouts.

The Patriots have pulled off some impressive patch jobs before on defense, most notably in 2004, when the secondary was working on a wing and a prayer, so it can be done.

Now, in what is now their three-game season, it’s a question of how.

smanza@projo.com