CLEVELAND — LeBron James scored 23 points, Delonte West had 13 and a career-high eight steals and the Cleveland Cavaliers became the first team to clinch a spot in the NBA playoffs by beating the Milwaukee Bucks 91-73 on Wednesday night in a potential first-round series preview.

At 48-12, the Cavaliers wrapped up their fourth straight postseason berth with more than one month left in the regular season. But Cleveland has been doing everything at an accelerated rate. The Cavs moved 36 games over. 500 for the first time and improved their league-best record at home to 27-1.

Mo Williams scored 15 against his former team and Zydrunas Ilgauskas added 14 for Cleveland, which lowered its magic for winning the Central Division to six.

Richard Jefferson scored 29 for the Bucks, currently clinging to the No. 8 spot in the Eastern Conference.

Cleveland swept the four-game season series between the teams, who could meet again in April with more more at stake.

Milwaukee was still within striking distance late in the third quarter, but Wally Szczerbiak hit a 3-pointer and James followed with one of his own as the Cavs, who seemed disinterested for much of the night, took a 14-point lead into the fourth.

The Bucks fought back and closed within 10 when James, who scored 55 in the last meeting between the clubs, dropped a step-back 3-pointer over Luc Mbah a Moute in the deep corner near Milwaukee's bench to make it 81-68 with 6:45 left. James paused to admire his make before heading down the floor.

Cleveland was back home following a grueling, four-games-in-five-nights road trip during which the Cavs went 3-1 against Houston, San Antonio, Atlanta and Miami — all likely playoff teams. Cleveland had to rally to win the last two games, and overcame lengthy travel delays en route to South Florida.

The Cavs didn't have to work nearly as hard against the Bucks.

As he was being stretched out by a trainer on the locker room floor before tipoff, James, Williams and teammate Tarence Kinsey watched the video of James' 55-point performance against the Bucks on Feb. 20. James seemed to recall every dribble, pass and shot and was most impressed by his 24-point, third-quarter explosion.

"That's the best quarter I've ever seen," he said.

There would be no encore for James, who attempted just 11 shots and sat out the final four minutes.

Ahead by just three points in the second quarter, the Cavaliers went on a 9-0 run capped by a 3-pointer from James and opened a 48-39 halftime lead.

Jefferson kept the Bucks close all by himself as he scored 17 points in the opening half.

Notes: The Cavs are expected to officially sign F Joe Smith on Thursday. Smith, who played in 27 games for Cleveland last season, recently bought his contract from Oklahoma City for a chance to play with a title contender. He has agreed to terms on a one-year deal with the Cavs. ... It's been a record-setting season for Cleveland, which has won just one division title in its less-than-spectacular 39-year hoops history. James was asked if he was surprised there has been so few crowns in his lifetime. "There's a lot of stuff that's happened around here this year that's hasn't happened since I was born," James said. "It's always nice to make history." ...The Cavs will play 10 home games in March, including eight of their last nine. ... Jefferson has made 31 straight free throws.