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There is a changing of the guard at the top of the NBA Power Rankings for the first time this season. It might be temporary, but a chain of recent events suggest it is warranted.

Moving the Los Angeles Lakers ahead of the Boston Celtics would have been easier had the Lakers taken care of business Sunday against the Phoenix Suns. Instead, they suffered a loss, as did the Celtics against the Pistons in Boston.

Even so, a couple of factors work in the Lakers' favor and a couple work against Boston. Chief among them is that their quality of play over the past couple of weeks has been better than that of the Celtics, who suffered road losses to the Los Angeles Clippers and Utah Jazz over the past week.

What's more, the Celtics clinched their move down to second with the seemingly unnecessary and potentially damaging signing of Stephon Marbury.

Here are the NBA Power Rankings through March 1:

1. Los Angeles Lakers (48-12) - Despite two straight losses, the Lakers have still won seven of their past 10 overall, which includes a six-game winning streak prior to the recent skid. They have generally appeared in postseason form, as Kobe Bryant continues to improve the team's overall balance by picking his spots in which to take over games, while delegating this role to Pau Gasol, Lamar Odom and others as warranted.

2. Boston Celtics (47-14) - For a front office and head coach as shrewd as the Celtics and Doc Rivers, the signing of Marbury makes no sense. If they wanted a backup point guard with leadership and proven experience, they should have kept Sam Cassell. Marbury is the Terrell Owens of the NBA; he's proven to be a cancer at every stop in his career.

3. Cleveland Cavaliers (46-12) - The Cavaliers have refused to back down from their quest to become one of the league's elite clubs, as they are in the midst of another impressive run on the court and at the sports book. The Cavs have won seven of their past eight and brought gamblers the cash in six of those wins.

4. Orlando Magic (43-16) - Despite a home loss to the Pistons, the Magic appear to be back near top form after acquiring Rafer Alston for the stretch run. They have won two straight road games, and their 37-21-1 mark ATS this season helps them remain among the league's most profitable teams.

5. San Antonio Spurs (39-18) - The Spurs are simply in hold-steady mode while awaiting the return of Tim Duncan and Manu Ginobli from injuries. Panic is never in the equation for this club, which you can count on for a late surge once the Big Three return to full strength.

6. Denver Nuggets (39-20) - The inconsistent Nuggets have left their backers mostly with crumbs of late, covering just once in their past six outings while posting just two wins in that span.

7. Houston Rockets (37-22) -Tracy McGrady's season - and perhaps his tenure - in Houston is over which, amid all the uncertainty constantly swirling around their fragile star, might be the best-case scenario for the Rockets.

8. Utah Jazz (36-23) - The erratic Jazz are back rolling at the right time, with wins in nine of their past 10 and eight cashes along the way to support their late-season surge into what they hope will be a top-four seed in the Western Conference.

9. Dallas Mavericks (36-23) - Dirk Nowitzki, Jason Kidd and friends continue to push the new-look Mavericks into contention. But their improved defense has meant a halt to their once high-scoring ways, and they have brought home the money just three times in their past 10.

10. Portland Trailblazers (36-22) -Still looking for a second star to complement Brandon Roy, the Blazers came up short against Houston and San Antonio on their recent road swing, proof that their building project is still a work in progress.

11. New Orleans Hornets (35-22) - Although New Orleans' dynamic run in last year's playoffs set the bar higher than hey could reach this year, the Hornets have been far from a disaster. They have won four straight, but the bad news for gamblers is that they have missed the cash in five consecutive games.

12. Atlanta Hawks (33-26) - Atlanta has taken the cash in three straight, but losses in five of their past seven have hindered their effort to improve on last year's playoff run. Sunday's loss to the Cavaliers is the type of game they need to win to be taken seriously.

13. Phoenix Suns (34-25) - Sunday's 118-111 win over Lakers might have been the best all-around effort the Suns have displayed this year. But injuries to Steve Nash and Amare Stoudemire, combined with the coaching carousel that left Alvin Gentry at the helm, are likely too much to overcome for Phoenix to make the playoffs.

14. Miami Heat (31-27) - The Heat can't quite seem to pull away from the pack of mediocre teams in the Eastern Conference, but at least they have been consistent. They have alternated one win with one loss in splitting their last 10, but have taken the cash just three times.

15. Detroit Pistons (29-29) - Surprising back-to-back road wins over Orlando and Boston shows what Detroit is capable of but, unfortunately, these wins will just serve as a nice sidebar on a lost season.

16. Philadelphia 76ers (29-29) - A lack of firepower has hurt Philadelphia's climb to contention, as the league's 24th-ranked offense has plodded through losses in five of their past seven.

17. Milwaukee Bucks (29-33) - The Bucks have remained surprisingly solid amid the losses of Andrew Bogut and Michael Redd to injury. Their 35-25-2 ATS mark indicates that they still provide some value at the sports book.

18. Chicago Bulls (27-33) - Although the Bulls won't turn the corner until they address their frontcourt issues, one bright spot lost in this disappointing season is that Ben Gordon is one of the game's underrated stars. He leads Chicago with 20.5 points and 3.5 assists per game.

19. New Jersey Nets (26-32) - Devin Harris' half-court heave to beat Philadelphia after bobbling the ball might go down as the greatest NBA buzzer-beater this season. At least the Nets will be remembered for something.

20. Charlotte Bobcats (25-35) - You could make the case that Charlotte has the most promise of any team currently under .500. Larry Brown will maximize the talent of his young core, and all the Bobcats need is a little more firepower to improve the league's worst offense (92.8 points per game). They have won and covered in three straight, and have taken the cash in seven of their past 10.

21. Indiana Pacers (25-36) - The Pacers have held things together reasonably well despite injuries to Mike Dunleavy and All-Star Danny Granger. They have won six of their past 10 and covered in seven of those.

22. New York Knicks (24-35) - With players like Nate Robinson and David Lee leading the way, the Knicks might be the most exciting bad team in basketball, stealing the crown from Golden State's grasp of late.

23. Toronto Raptors (23-37) -Nothing stands out as the primary cause of woe for the Raptors; they simply are consistently below average in all facets of the game and are in need of a roster overhaul.

24. Golden State Warriors (20-38) - Despite recent efforts by the Clippers and others, Golden State refuses to relinquish its role as the NBA's worst defensive club, allowing access to their own basket at the possibly record-setting pace of 111.6 points per contest.

25. Minnesota Timberwolves (18-40) - Al Jefferson's season-ending injury predictably put a limp in Minnesota's effort to step forward; the Wolves have lost nine of their past 10 and have only brought home the cash twice in that span.

26. Memphis Grizzlies (15-43) - The lumps keep coming for the Grizzlies, who have lost seven straight with just three covers in the mix. The good news is that rookie O.J. Mayo has proven to be a solid pick, as he leads the team with 19.2 points per game.

27. Oklahoma City Thunder (14-45) - Interesting note that the Thunder broke their seven-game losing streak with their best player, Kevin Durant, out with an injury in Saturday's win over the Grizzlies.

28. Los Angeles Clippers (15-45) - Last week's home win over the Celtics as a 10-point underdog was perhaps the biggest milestone of the season for the lowly Clippers, who otherwise haven't given their fans much to cheer about.

29. Washington Wizards (14-45) - There has been some debate of late as to how much Gilbert Arenas would have helped this team if he were healthy. Not enough to make much of a difference in this observer's view.

30. Sacramento Kings (13-48) - The good news for Kings fans courageous enough to bet their team is that they have covered in six of their past eight outings. The bad news, as is often the case these days, is that six of those eight efforts resulted in another mark in the loss column.