NBA: Win or bust for James and Heat as playoffs begin

The Miami Heat and LeBron James begin an all-or-nothing campaign for an NBA title while defending champion Dallas Mavericks and Kirk Nowitzki face a tough start to the opening weekend of the playoffs.

Second seed Miami (46-20) host the New York Knicks (36-30) and high-scoring Carmelo Anthony in their first-round opener on Saturday as Dallas (36-30) go up against second-seeded Oklahoma City Thunder (47-19).

Eight playoff series kick off on Saturday and Sunday as the grind of a 66-game NBA season compacted by the league's labor contract dispute gives way to the spotlight of best-of-seven series on the road to the title.

Eastern Conference top seed Chicago Bulls (50-16) play the Philadelphia 76ers (35-31), and their Western Conference counterparts San Antonio Spurs (50-16) take on the Utah Jazz (36-30) in a series opener on Sunday.

After James joined fellow free agents Dwyane Wade and Chris Bosh prior to last season to form a Big Three in Miami, the trio hoped to bring a bundle of NBA titles to South Beach.

The partnership nearly paid immediate dividends before Nowitzki and the Mavs denied them in the Finals in six games.

Now, nothing less than the NBA crown will validate the 2011-2012 campaign as a success for the Heat.

James, a leading candidate for MVP honours after averaging 27.1 points, 7.9 rebounds and 6.2 assists, may have a larger burden to bear as Wade is playing with a dislocated finger on his left hand and Bosh has been slowed by a hamstring injury.

The Bulls and Spurs should have smoother sailing against weaker opposition, though Chicago has had to manage with an injury-slowed Derrick Rose, last year's league MVP.

San Antonio, meanwhile, have been revitalized by an infusion of youth to augment their big three of Tim Duncan, Manu Ginobli and Tony Parker and are determined to make up for last year's first-round ouster by the Memphis Grizzlies.

Kobe Bryant and the Los Angeles Lakers (41-25), seeded third in the West, are favourites against the Denver Nuggets (38-28), but will be without rugged defender Metta World Peace, who has six games remaining on a suspension after he clobbered Oklahoma City's James Harden with an elbow to the head.

The Los Angeles Clippers (40-26) are eager to buck their long history of failure when they launch their playoff bid against Memphis (41-25).

A season-ending back injury to center Dwight Howard has crippled the chances of the Orlando Magic (37-29), who go up against the solid Indiana Pacers (42-24), seeded third in the East.

The evergreen trio of Kevin Garnett, Paul Pierce and Ray Allen, directed by lightning-quick point guard Rajon Rondo, surged down the stretch to give the Boston Celtics (39-27) hopes for a playoff revival against the Atlanta Hawks (40-26).

Photograph: Mike Ehrmann/Getty Images