NBA

Nets shock Celtics, extend win streak to five

The Nets were held to just .397 shooting and 88 points by Boston last night. And still they beat the Celtics by nine.

Again, they beat the CELTICS. Not the Raptors. Not the Warriors. Not the Clippers. The Celtics.

Maybe it won’t send the Earth off its axis or lower the price of gas, but the Nets running their winning streak to five games with an 88-79 victory over the reigning Eastern Conference champs is worthy of notice.

“It says a lot. For us to beat a team of this magnitude, that’s a big hurdle for us,” said coach Avery Johnson after the Nets (22-43) moved to with 5 ½ games of a playoff spot with 17 games to play.

The bench praised the starters; the starters praised the bench and everybody praised the defense, even the guys who combined for 11 3-pointers.

That defense held the Celtics (47-18) scoreless after Glen Davis (16 points) nailed a jumper at 3:09 to cut the Nets’ lead, as high as 12 at 9:33 when Travis Outlaw (12 points) banged in a triple, to just two.

“Hopefully it can get our confidence going. We had those four wins, two of which I wasn’t a part of and those were good wins — you don’t want to take anything away from a win, ever — but they weren’t against playoff teams,” said Deron Williams (16 points, nine assists, six rebounds).

Williams returned from a two-game absence for the birth of his son in time to bring toughness and the game’s dagger shot, a 3-pointer at :35.6 to go up seven — after he fed Brook Lopez for a jump hook and a four-point spread at 1:14.

“And this is the best team in the East,” Williams said, “the team with the best record. We battled, we played good defense, especially down the stretch. We had to.”

Again, that defense stuffed the Celtics on their final six shots while the Nets were rolling up just enough the other way to make the NBA perhaps take notice and to disappoint most in the pro-Boston gathering of 18,711 — the season’s third Newark sellout.

“It felt great. This was the best win of our five games,” raved Kris Humphries, who again was a mauler inside (16 points, 15 rebounds, seventh straight double-double, his 23rd of the season).

“I can’t say enough about the bench. It really was the bench’s game,” said Lopez (20 points).

For a time, it looked as if it would be the bench’s game — garbage time. In the first quarter, Boston ran off the final 14 points for a 23-14 lead.

The Nets got back to within two by the half and then with a small, bench-inspired lineup, scored 31 points in the third quarter. The period ended with Sundiata Gaines, the 10-day-contract find, hitting a 3-pointer from the banks of the Passaic River at :01.6 for a 67-61 lead.

“It gave us a boost,” said Gaines.

Said Johnson, “That 3-pointer, it kind of carried some momentum into the fourth quarter.”

And from there, the Nets used a suffocating defense to snuff the Celtics, who had fought foul trouble and poor shooting all game — Paul Pierce was 2 of 10 for seven points, for example, and Rajon Rondo was 1 of 10.

“They made their shots. We couldn’t get a stop when we needed it,” said Kevin Garnett (18 points, eight rebounds). “They have been playing well lately with a lot more energy. D-Will has come over there and given them a winning mentality.”

And they know it.

“We’re playing good right now,” Williams said. “I think we’re gelling pretty well for having such a short time together, and having fun.

“These games are important right now, not only because we have a chance for the playoffs, but just for the future, and going forward next year.”

fred.kerber@nypost.com