Brook Lopez, the Nets' newly minted All-Star center, potentially will face a tough test during tomorrow night's high-profile game in Brooklyn against Dwight Howard and the star-studded Lakers. Howard missed the Lakers' game yesterday at Detroit due to an ailing shoulder, and hinted he might not be ready to play tomorrow either. If he does play, however, he will offer a tough test for Lopez. Howard has dominated Lopez as often as he has turned up in trade talks about him. "It's always a good benchmark for me. It's definitely a matchup. You've got to match [Howard's] energy. He's very athletic, very strong,'' said Lopez. "It's always a fun game against them. It's a good challenge for us as a team and myself personally. It's a good benchmark.'' Lopez has reached new benchmarks this season, especially regarding his much-maligned defense. His 7.2 rebounds per game are his most since his second year in the NBA, and his career-high 2.18 blocks per game are sixth-best in the league. "Comparing it to two years ago, the difference ... is his commitment to defense. He's a factor impacting shots, not just on his man but on penetration,'' said interim coach P.J. Carlesimo. "It's just night and day. His attention to defense is so much better than it was, and it's helped our team defense significantly. "It's something [former coach] Avery [Johnson] asked and we've asked him to focus on, and he's done it. ... This year we said 'Brook, we've got to block more than two shots a game.' And he's done it right from the beginning, so it's been great.'' Point guard Deron Williams — expected to play despite spraining his ankle Friday against Chicago — said Lopez's defense has improved simply from having to go against Andray Blatche in practice daily, but in the end, it has come down to an attitude adjustment. "He came with a new attitude this year,'' said Williams. "He knows how much we needed him on the defensive end, especially holding down the paint, getting blocked shots, altering shots, and he's done a great job of that, as well as rebounding.'' Lopez had the reputation as a soft player, but after coming into the NBA at 265 pounds, has packed on muscle and weighed in yesterday at 281. "I just want to be there to help my teammates out, whether it's blocked shots or [help defense]. All the good defensive teams have a good big man in the middle, and they trust each other,'' Lopez said. "A lot of it was [being more aggressive]. A lot of it was watching film and really getting timing down. You watch yourself and what you're doing wrong, as much as teams playing defense the right way.''