Indiana Pacers (3) vs. Orlando Magic (6)
Season series: Magic 3-1
Key matchup: Danny Granger (Pacers) vs. Quentin Richardson (Magic). Richardson usually draws the opposition's top scorer. In this case, it's Granger, who averaged 19.3 points in the teams' four games.
X-factor: Tyler Hansbrough (Pacers). With the Dwight Howard-less Magic undersized, the 6-foot-9 reserve forward has a chance to match his performances in the past two meetings, when he averaged 18 points.
Miami Heat (2) vs. New York Knicks (7)
Season series: Heat 3-0
Key matchup: LeBron James (Heat) vs. Carmelo Anthony (Knicks). Perhaps the marquee duel in the first round, matching the longtime friends from the 2003 draft class. Anthony's sizzling April, in which he scored 29.8 per game, was built largely against slower power forwards. But James held him to only two baskets in the fourth quarter of the teams' most recent meeting.
X-factors: J.R. Smith and Steve Novak (Knicks). New York needs its perimeter shooters to get hot off the bench if Anthony and Amare Stoudemire are going to get the room they need.
Chicago Bulls (1) vs. Philadelphia 76ers (8)
Season series: Bulls 2-1
Key matchup: Luol Deng (Bulls) vs. Andre Iguodala (76ers). Iguodala led the defensive effort against the fellow All-Star as Deng shot 3 for 11 in both games he played and averaged seven points. Iguodala scored 19 in the 76ers' win but totaled only 21 in the losses, going 3-of-10 from the field for seven points in the final matchup.
X-factor: Joakim Noah (Bulls). The ex-Gator had only two points and two rebounds in Chicago's loss but averaged 12 and 14.5 as it took the last two meetings.
Okla. City Thunder (2) vs. Dallas Mavs (7)
Season series: Thunder 3-1
Key matchup: Russell Westbrook (Thunder) vs. Jason Kidd (Mavericks). The Thunder's biggest struggles often come on Westbrook's poor shooting nights. But Kidd, 39, will need help to force the point guard into them.
X-factor: Brandan Wright (Mavericks). The reserve forward, 24, is one of the few Mavericks with young legs, and they will be needed to keep up with the much quicker Thunder.