PER Diem: March 16, 2009

We're nearing a very interesting time of year in the Playoff Odds, because so few games remain that a single surprising win or surprising loss could shift a team's probability rather sharply.

And we got plenty of evidence for that this past weekend. Take Charlotte, for instance, whose odds to earn the 8-seed were cut basically in half in a single night after the Bobcats fell to lowly Minnesota while the Bulls were putting together a surprisingly easy win over the Hornets. Milwaukee and Phoenix, on the other hand, saw their chances boost significantly after big wins on Sunday.

Several other races changed sharply this past weekend in the wake of a few surprising results. Let's take a closer look at the ones of greatest interest:

Nos. 7 and 8 in the East: Coming into the weekend, the Sixers looked like less than a sure thing to make the postseason as the East's No. 7 seed, and the No. 8 seed seemed a two-horse race between the Bulls and Bobcats.

Now? The Sixers are almost a lock, having improved their odds to 87.2 percent after solid wins over the Bulls and Heat. In fact, the Sixers' odds now mirror those of the Pistons after Detroit's shocking home loss to lowly Memphis on Sunday. The Pistons lost at home to both the Knicks and Grizzlies in the past week and have several losable games left on the schedule.

The push for the No. 8 seed is back to being Chicago's race to lose. Although the Bulls are effectively tied with Milwaukee in the standings, Chicago has 10 home games left against just five road games, and only six of the games are against teams with winning records. Chicago's 59.1 percent playoff odds are nearly triple those of their closest foil, the Bucks. Remember, Chicago has the tiebreaker with Milwaukee after winning the season series 3-1.

Milwaukee's upset of Boston on Sunday has moved the Bucks into the likely No. 9 spot and pushed their odds up to 21.0 percent. They aren't higher because they'll still play Orlando three times and the Lakers once, and because they'll have to beat out Chicago by a game thanks to the tiebreak situation.

Further down, the Bobcats' loss to Minnesota on Saturday was a killer, pushing their odds down to 17.3 percent. New York, though, has played extremely well of late and remains a long shot at 14.9 percent.

No. 2 in the East: Forget about catching Cleveland, Celtics fans. After Sunday's loss to Milwaukee, Boston has only a 7 percent chance to earn the top seed. Instead, it should worry about Orlando. The Celtics and Magic are tied in the loss column after Boston went 4-5 during its past nine games while Orlando went 8-1. Additionally, the Magic's robust wins over Chicago (107-79) and Utah (105-87) boosted their Power Ranking significantly.

The Magic still project to finish two games worse than Boston thanks to a more difficult closing kick. But factoring in that the playoff odds don't know of Boston's injury problems, we can look for this race to go down to the wire.

No. 8 in the West: No, it's not over, as I keep reminding people. And it's especially not over after this past weekend. Phoenix's odds are back up to 33.1 percent after it beat Golden State and Oklahoma City while Dallas lost to the Warriors and Lakers. This may seem unusual because the Suns still trail the Mavs by four games in the standings, but Phoenix will close with a much easier schedule and can put a huge dent in the gap with a win in Dallas next month.

Additionally, the odds that Phoenix could catch a team other than Dallas are nearly as great as the Suns' chances of catching the Mavs. Neither the Jazz (94.9 percent) nor Blazers (94.1) are out of the woods after both had tough trips through the Southeast this past weekend, though the Mavs (83.1) have by far the lowest odds of the West's top eight.

Northwest Division: San Antonio's win in Houston on Saturday probably ended the division race in the Southwest. The Spurs are now 80.5 percent likely to win the division, and New Orleans (11.7 percent) probably needs to sweep the final two meetings between those teams to claim the crown.

That leaves the Northwest as the only undecided division, and what it makes it more interesting is that three teams still have roughly equal odds of winning it. Denver (42.2 percent) is back in the catbird's seat after the road woes of Portland (32.4) and Utah (25.5) this past weekend, and it still looks as though it may come down to the Blazers-Nuggets meeting in Portland the last day of the season.

John Hollinger writes for ESPN Insider. To e-mail him, click here.