Lopez ranks second in blocks per game during the 2013 playoffs, behind Oklahoma City's Serge Ibaka (3.5 to 3.4).
According to ESPN Stats & Information, the Nets are giving up just 95.5 points per 100 possessions against the Chicago Bulls with Lopez on the court, compared to 118.9 without him.
"I just think I really have to attribute that to our team defense," Lopez said. "We've been improving as the year's gone on, and our trust levels have gone up as well."
Asked if he has been more aggressive on defense, Lopez responded, "Definitely. I'm that last line of defense."
Last season, Lopez played just five games due to a foot injury. "I'm honestly happy to be playing," he said. "It sucked to not be on the floor playing with my teammates. I wanted to get in a place where I wouldn't be able to get injured again and go out there and be able to play basketball and have fun."
In the postseason (five games), he's averaging 23.6 points and 8.0 rebounds on 49.9 percent shooting.
Power forward Reggie Evans recently referred to Lopez as a top-two center in the league.
"That's a huge honor," Lopez said. "Obviously it’s great to hear from a teammate and legends like Shaq and Charles Barkley. I'm very proud of that and I thank them for the compliment."
Lopez had his right ankle taped because of stiffness, but said he's fine. The Bulls will play Game 6 in Chicago at 8 p.m. Thursday, their second consecutive elimination game.