Boston Celtics’ Paul Pierce (L) collides with Miami Heat’s Dwyane Wade during the first quarter of NBA basketball action in Miami November 11, 2010. Pierce was called for an offensive foul on the play. REUTERS/Hans Deryk (UNITED STATES – Tags: SPORT BASKETBALL)

The 16 playoff spots are locked up, so all that’s left is to narrow down these first round matchups. The only matchups that are set are CHI/IND and ORL/ATL in the East. Here are the probable first round matchups as it stands on Saturday, along with my own estimation as to how likely they are to actually happen.

EAST

#1 Chicago vs. #8 Indiana (100%)

#4 Orlando vs. #5 Atlanta (100%)

#2 Miami vs. #7 Philadelphia (55%)
Boston and Miami square off on Sunday and the winner will be in the driver’s seat for the #2 seed. That’s important because the #2 seed will host Game 7 of a potential MIA/BOS matchup in the second round. It’s also important because Miami is 0-3 against Boston this season and needs to psychologically get it together if they hope to beat the Celtics in the postseason. The good news for Miami is that the C’s just aren’t the same since the Perkins trade. But we’ve learned not to underestimate Kevin Garnett, Paul Pierce and Co.

#3 Boston vs. #6 New York (55%)
This might be the matchup that the C’s would rather see since they’ve handled the Knicks in their one post-trade matchup with the new-look Knicks. The Sixers have given the Celtics problems this season. (Their first three games were decided by a total of eight points.)

WEST

#1 San Antonio vs. #8 Memphis (65%)

The Grizzlies and Hornets play on Sunday in Memphis and if the Grizzlies win, they’ll be in a tie with New Orleans for the #7 spot. But the Hornets would still own the tiebraker (division record). Plus, I’m not even sure Memphis wants to win and increase the chances of facing the Lakers in the first round.

#4 Oklahoma City vs. #5 Denver (85%)
The Thunder could conceivably catch the Mavericks, though Dallas own the head-to-head tiebraker, so OKC would have to make up two games on the Mavs to overtake them. Denver could conceivably slip out of the #5 spot, but the Nuggets hold a 1.5-game lead on the Blazers. (Portland does own the conference tiebraker, however.)

#2 L.A. Lakers vs. #7 New Orleans (65%)
This assumes the Grizzlies can’t catch the Hornets. I doubt Memphis is too motivated — wouldn’t both teams rather face a reeling Spurs team than the defending champs?

#3 Dallas vs. #6 Portland (85%)
Dallas could slip out of the #3 spot while Portland could catch #5 Denver or slip into the #7 spot if the Hornets get hot. The Blazers only have two games left, but one is against a fairly hot Memphis team.

For an overview of the playoff race, check out CBSSports.com.