Roberto Luongo came to the Islanders with a week’s worth of clothes. But now he’ll be with the team longer than expected.

Luongo, the 20-year old rookie goaltender, was called up from the team’s AHL affiliate in Lowell on Nov. 22, the day after backup goalie Wade Flaherty was diagnosed with a strained right shoulder he suffered in practice. Flaherty was supposed to be out a week to 10 days, but the team announced yesterday that his shoulder is actually sprained, which will put him out indefinitely, and keep Luongo with the club.

Luongo remained on the bench for the finale of the Isles’ three-game road trip (1-1-1) as Felix Potvin manned the nets. Though Luongo didn’t start against the Caps at the Coliseum last night, either, there’s a chance he could start tonight when the Islanders visit the Bruins at the FleetCenter.

Isles coach Butch Goring was non-committal when he was asked after the morning skate yesterday if Luongo would play against Boston. But he did say that it was senseless for Luongo not to receive any NHL experience while he’s with the team.

“It won’t do Luongo any good to sit,” Goring said.

Luongo, the Isles’ first round pick (fourth overall, the highest- drafted goalie in history) in the 1997 entry draft, said he’s eager to see some action.

“No matter when it is or where it is, it’ll be exciting,” Luongo said.

Luongo’s performances had created enough excitement during training camp that Goring said he had a strong chance to make the team. But when the team backed off on plans to trade Potvin and his $2.7 million salary this season, Luongo was sent to Lowell as opposed to having him get rusty as a backup.

In 15 games with the Lock Monsters, the agile 6-foot-2, 176-pounder was 6-6-3 with a respectable 2.98 goals-against-average and a .906 save percentage.

“My confidence is still there,” he said. “I feel like I did in camp.”

Defenseman Kenny Jonsson said he’s impressed with what he’s seen from Luongo so far.

“He looks very sharp in practice,” Jonsson said.

By tasting the NHL experience, Luongo could get used to this life very fast. If anything, it sure beats playing in Lowell.

“There’s not much there,” Luongo said.

D Eric Brewer is out two to three weeks with an injured toe. Brewer suffered the injury Nov. 19 at Colorado … D Kenny Jonsson, who scored his first goal of the season and added an assist against Edmonton last Tuesday, said he is happy to be paired again with D Rich Pilon, who returned from a knee injury during the Isles’ three-game trip.

“It helps because we played together for a long time and we can read off each other really good,” Jonsson said. “I know he’s very physical so I don’t have to concentrate on hitting people. He’s doing that.”

Jonsson, the team’s captain, has occasionally publicly criticized his teammates this season for their lack of desire. But coming off the Isles’ 1-1-1 trip, Jonsson said he feels the team is turning the corner.

“We’re playing a lot better,” he said. “We’re working harder together as a group than we did. We’ve started to understand what it takes to win.”

The Isles began last night a brutal stretch of their schedule with 16 games (11 at home) in 33 days.

“If we want to get back in the playoff hunt [December] is the month to do it,” Goring said.