BOSTON – The resumes and statistics say Richard Jefferson and Jason Collins have been around for two seasons.

Their play and poise say something else.

“Twin [Collins] acts like he’s been in this league a long time with all the ice he puts on his body,” Jason Kidd said.

But it’s more than ice packs and aches that show what Collins and Jefferson have gone through and what they mean to the Nets, who tried to claim a suffocating 3-0 lead over the Celtics in the Eastern Conference semifinals last night inside the expected hornets nest, FleetCenter.

Jefferson, 22, and Collins, 24, who both came to the Nets in the pivotal 2001 draft night trade with Houston, claimed starting positions this season. Collins began on the bench then took over at center when Dikembe Mutombo went down with a wrist injury in November. Collins, who played with a sprained left wrist last night, is the master of all those things that don’t show up in the box score. He has developed into one of the league’s best help defenders at his position. He blocks out. He is a super passer out of the post.

“Two years? It seems like more,” said Collins, averaging 6.8 points and 6.6 rebounds in the playoffs. “We’ve played in a lot of big games the first two years, there’s a lot of experience for us to fall back on.

“In two years I’ve played more basketball than probably all my life,” Collins added. “The amount of games and practices and stuff, but I’ve made it through it and I’m doing well.”

Jefferson hasn’t been too shabby, either. He was the reason behind the trade of Keith Van Horn for Mutombo. The Nets had to get Jefferson playing time. He had a starter’s skill on the bench. He got the small-forward’s job and has not stopped paying dividends. His 25 points were the difference in Game 2 of this series. He is shooting a phenomenal .542 in the playoffs as the Nets’ No. 3 scorer (16.1) behind Kidd and Kenyon Martin.

Jefferson credits his teammates for much of his growth.

“My maturity grew through the way J-Kidd and Kenyon and Kerry [Kittles], Dikembe and Rodney [Rogers], the coaching staff have helped me. I’ve had great teammates,” Jefferson said. “I’m the youngest guy on this team. I’ve been blessed.”

Teammates feel they’ve been blessed with the two young guys.

“When you’re willing to listen and learn that helps,” Rogers said. “RJ is a young talent – still has a long way to go – but the things he’s doing are good for us and for him. Jason Collins, the guy is a workhorse. That’s what we need.”

Jefferson related how Kidd even forgets the real depth of his teammate’s experience.

“J-Kidd sometimes says to me, ‘If I get [angry] because you’ve had a couple bad games, don’t mind me. I forget this is your second year in the league. Know what I was doing my second year? I was about to get traded. We ask so much of you, just keep working,’ ” Jefferson said. “Not many guys can say they’re in the position I’m in, in my second year. Competing for a championship, there is no night to have a bad game because your team will struggle.”