The Houston Rockets’ best player is out for the season, but you wouldn’t know it by watching them play. The team has vanquished three more opponents since Yao Ming checked out with a stress fracture in his foot, running its winning streak to 15 games — the longest in the NBA this season.

They’re not winning nail-biters, either. Houston routed Memphis, Washington, and Denver by a combined 60 points to move up to a tie for the fourth-best record in the Western Conference, a half-game behind New Orleans for the no. 3 spot. With a fairly soft schedule the rest of the way and a lineup that’s clicking on all cylinders, the Rockets could end up with home court advantage in the first round of the playoffs even without Yao.

The reason Houston has been so effective is that it’s no longer a two-man team. In fact, both Tracy McGrady and Yao have had their worst season in the past four this campaign, at least based on my Player Efficiency Rating (PER, a per-minute rating of a player’s statistical effectiveness).

However, the secondary players have been much better than in previous seasons. Rookie power forward Luis Scola solidified a glaring weakness, averaging 12.4 points on 59.9% shooting since taking over the starting job from Chuck Hayes. And rookie Carl Landry has been a huge force off the bench — his numbers don’t seem that great until you realize they come out to 20 points and 12.5 boards per 40 minutes and he’s shooting 64.1%.

Of course, they’ll need the rest of the gang to stay healthy — losing the oft-injured McGrady in particular would be devastating — and they’ll need to keep up the impressive esprit de corps they’ve shown in rolling to 19 wins in their past 20 games. But at this moment, even without Yao, they rate as one of the league’s top five teams — and that’s reflected in their no. 5 position in this week’s list.

On to the rankings:

1. LOS ANGELES LAKERS (42–18) (LW:1): Kobe Bryant enhanced his MVP case with a 52-point masterpiece on national television on Sunday, but in my book, LeBron James has been the superior player this season.

2. DETROIT PISTONS (43–16) (2): The team blew an 18-point lead in Utah to mar what would have been a perfect four-game Western trip, but they added shot-blocker Theo Ratliff to an already imposing frontcourt.

3. BOSTON CELTICS (46–12) (3): Kevin Garnett came back just in time, as the Celtics face a showdown tomorrow against their top Eastern rival, Detroit.

4. SAN ANTONIO SPURS (41–17) (5): Brent Barry’s decision to rejoin San Antonio after being waived by Seattle felt fishy to some other Western teams; by rule, he’ll need to wait 30 days before suiting up again.

5. HOUSTON ROCKETS (39–20) (7): Another unsung hero of the Rockets’ recent rampage has been point guard Rafer Alston. His offense remains spotty but his D is exquisite, as he showed while frustrating Denver’s Allen Iverson Sunday.

6. UTAH JAZZ (38–22) (4): You know you’re good when you’ve won six of 10 and everybody’s asking what’s wrong. The Jazz have hit a little bump, but I wouldn’t get too worried just yet.

7. ORLANDO MAGIC (38–23) (10): The bane of the locals this week, as they squashed both the Knicks and Nets — but they handed a win to one of Jersey’s competitors for a playoff spot when they lost to Philly.

8. DALLAS MAVERICKS (39–21) (9): The most annoying trend of the Kidd-in-Dallas era is announcers crediting every good pass by other Mavs to the magic dust thrown off by Kidd.

9. NEW ORLEANS HORNETS (39–19) (6): It’s tough to take the Hornets seriously as an elite Western team when they lost to the Wizards without Gilbert Arenas and Caron Butler — twice. But at least Chris Paul finally got the better of Utah’s Deron Williams this week.

10. TORONTO RAPTORS (32–26) (8): Even allowing for Chris Bosh’s absence, the Raps’ losses to Indiana and Charlotte were horrid, embarrassing affairs. The hope is for CB4 to be back in a week.

11. DENVER NUGGETS (35–24) (14): The team is hanging on for dear life in the Western playoff chase, and its next four games (Utah, Phoenix, and two against the Spurs) threaten to push it off the ledge for good.

12. GOLDEN STATE WARRIORS (36–22) (13): Guard Monta Ellis blew up in February (26.0 points per game, 60.2% shooting); he’ll be needed even more this week as the Warriors embark on a four-game Eastern trip.

13. CLEVELAND CAVALIERS (34–26) (12): The LeBron Show comes to the Garden tomorrow night, but his team has been erratic of late while incorporating new faces and missing some old ones (Daniel Gibson, Sasha Pavlovic).

14. PHOENIX SUNS (39–20) (11): After Saturday’s home loss to Philadelphia, the Suns are 5–6 since trading Shawn Marion — even though eight of the games were at home. The mark could worsen with this week’s Blazers-Nuggets-Jazz-Spurs slate.

15. PHILADELPHIA 76ERS (27–33) (15): The Sixers have quietly moved into position to usurp a playoff spot, despite being the league’s worst 3-point shooting team. They can widen their advantage with three games against losing teams this week.

16. WASHINGTON WIZARDS (29–30) (17): The Wiz are nothing if not resilient, overcoming 15- and 18-point deficits on the road to beat New Orleans and Chicago, respectively — even with two All-Stars in civvies on the bench.

17. PORTLAND TRAIL BLAZERS (31–29) (18): Erratic point guard play has been one factor in Portland’s fall from contention out west, which is why the Blazers were pushing hard to deal for one at the trade deadline — including the Nets’ Devin Harris.

18. SACRAMENTO KINGS (27–32) (16): I liked them better when everyone was injured. Ron Artest and Kevin Martin are taking turns dissing coach Reggie Theus, but he may have earned it after taking shots at players through the press early this year.

19 ATLANTA HAWKS (24–33) (19): A report that general manager Billy Knight tried to fire head coach Mike Woodson, only to be turned down by ownership, adds another layer to the Hawks’ muddle

20. NEW JERSEY NETS (26–33) (20): An auspicious debut for Devin Harris, who produced 21 points in 21 minutes during a rout of Milwaukee. He’ll get his first shot at Jason Kidd on Saturday in Dallas, in the fourth of a crucial five-game swing for Nets.

21. CHICAGO BULLS (23–36) (21): An upcoming Cleveland-Boston-Detroit-Utah stretch could be a knockout blow for their playoff hopes. That is, if anyone else in the East wins a game in that stretch.

22. INDIANA PACERS (24–36) (22): Though Jermaine O’Neal and Jamaal Tinsley are sidelined, Indy is quietly scoring in bunches, combining for 250 on the Bucks and Raptors in the past two contests.

23. L.A. CLIPPERS (19–38) (23): The Clips agreed to a buyout with veteran guard Sam Cassell: Thus ends the brief era of competitive basketball for L.A.’s “other” team.

24. MILWAUKEE BUCKS (22–38) (24): If they’re going to make a playoff run, this is the week to start: Seattle, Portland, and Philadelphia visit the Bradley Center, and the Bucks probably need a sweep.

25. NEW YORK KNICKS (18–41) (24): Warm up those “Fire Isiah” chants: The Knicks have a four-game home stand this week, and all four teams have winning records.

26. CHARLOTTE BOBCATS (20–39) (26):Good news: Charlotte’s 32–0 advantage over Toronto in second-chance points in Sunday’s win was the biggest disparity since the league began tracking the stat in 1996. Bad news: The Bobcats still stink.

27. MINNESOTA TIMBERWOLVES (12–46) (25): The team offset the joy of an impressive 11-point win over Utah by blowing a home game against the rebuilding Sonics on Sunday.

28. SEATTLE SUPERSONICS (16–43) (28): An overtime win in Minnesota was the first game of an eight-game trip — and one suspects the last that ends in victory.

29. MIAMI HEAT (11–46) (30): The Heat are looking a little more lively with Shawn Marion, routing Sacramento on Tuesday and nearly repeating the effort Sunday — until they blew a 20-point halftime lead.

30. MEMPHIS GRIZZLIES (14–45) (29): They’ve lost six straight games by double figures. Short of stamping “We’ve given up” on the front of their uniforms, I’m not sure they could convey their disinterest more clearly.

jhollinger@nysun.com