Las Vegas ? Floyd Mayweather Jr. has returned to the ring in a big way with an unanimous decision over the smaller, lighter Juan Manuel Marquez.

In his first fight back from retirement and a 21-month absence, Mayweather knocked down the undersized Marquez in the second round and then peppered him with countless damaging shots to remain unbeaten in 40 pro fights.

Marquez was a 130-pounder just 18 months ago, but the Mexican champion moved up two weight classes to be Mayweather’s hand-picked comeback opponent. At Friday’s weigh-in, he was four pounds lighter than Mayweather, who paid a hefty six-figure penalty for missing the bout weight.

The size disparity was painfully obvious from the opening bell, but Marquez stayed on his feet for 12 one-sided rounds.

AUTO RACING

Dixon takes IndyCar lead

Motegi, Japan — Scott Dixon’s IndyCar series championship hopes got a huge boost at the Indy Japan 300, while Ryan Briscoe’s took a hit from a pylon at the end of pit lane.

Dixon won the next-to-last race of the season to move into first place in the standings ahead of Target Chip Ganassi teammate Dario Franchitti and Briscoe.

Dixon recorded his fifth win of the season by finishing 1.4475 seconds ahead of Franchitti at the 1.5-mile Twin Ring Motegi oval. He led 139 of 200 laps after starting from the pole, taking the lead for good on the 164th lap.

Briscoe went into Saturday’s race with a 25-point lead over Franchitti and a 32-point lead over Dixon, but saw his chances to win in Japan — and perhaps take his first championship — dashed by a miscue midway through the race.

After a slow start, Briscoe took the lead for the first time on lap 103 when Dixon and Franchitti pitted. Briscoe pitted on lap 106 just before a yellow flag came out after Mike Conway hit the wall at turn 4.

Busch bags truck victory

Loudon, N.H. — Kyle Busch held off Ron Hornaday and Kevin Harvick to win the NASCAR Camping World Truck Series race at New Hampshire Motor Speedway on Saturday. Busch had just enough fuel to survive, running out of gas as he made his way to Victory Lane.

BASEBALL

Greinke OK to pitch

Chicago — Kansas City Royals ace Zack Greinke, hit in his throwing arm by a line drive during his previous start, played catch Saturday and should be able to make his scheduled start Tuesday against Boston.

“As long as there are no setbacks, it will be Zack on his regular day,” manager Trey Hillman said. “He felt fine. There’s a little bit of swelling in his forearm. It’s continuing to go south. We hope that’s dissipated in the next 72 hours before Tuesday.”

Greinke, 14-8 this season with a major league-leading earned-run average of 2.14, was struck by a line drive off the bat of Detroit’s Miguel Cabrera on Thursday. After being hit in the fourth inning, he stayed in the game and pitched one more inning. He’s scheduled to throw a short side session today.

SOCCER

Wizards defeat Dallas, 3-2

Kansas City, Kan. — Jimmy Conrad atoned for two defensive mistakes with an 80th-minute goal, and the Kansas City Wizards earned their first home win since mid-June with a 3-2 victory over FC Dallas on Saturday night.

Kansas City (8-11-6) trailed 2-1 after 75 minutes, but Josh Wolff tied it in the 77th and Conrad’s sprawling header three minutes later gave the Wizards their first home victory since a 3-1 win over New England on June 12. Dallas (7-12-6) has won just once in its last five games.

GOLF

Haas, Price share lead

Conover, N.C. — Jay Haas and Nick Price shared the lead at the Greater Hickory Classic on Saturday, and 31 players were within six strokes of the leaders going into the final round at the Champions Tour event.

Haas, the 2005 winner, and Price are at 11-under 133 at Rock Barn Golf and Spa’s Robert Trent Jones course. Haas shot a 1-under 71, while Price — a three-time major winner on the PGA Tour — vaulted into contention with a 67.

Choi leads LPGA event

San Diego — Na Yeon Choi of South Korea shot a career best 9-under 63 on Saturday to take a two-stroke lead over compatriot Jiyai Shin in the Samsung World Championship at Torrey Pines.

Choi finished at 15-under 201 to tie the tournament’s three-round record that Annika Sorenstam set when she won here in 2002 and 2005. Choi began the day three strokes behind second-round leader Shin, who shot a 68.

NFL

Rice among nominees

Canton, Ohio — Jerry Rice and Emmitt Smith headline the preliminary list of modern-era nominees for induction next year in the Pro Football Hall of Fame. The list released Saturday includes 131 players, coaches and contributors.

Hall of Fame selectors will chose 25 semifinalists by Nov. 27, and 15 finalists by Jan. 7.

Voting will take place Feb. 6, the day before the Super Bowl.

Other modern-era nominees include Tim Brown, Herschel Walker, Cris Carter, Andre Reed and Sterling Sharp. Former commissioner Paul Tagliabue also is on the list.

PRO BASKETBALL

Kaun has herniated disc

Former Kansas University basketball center Sasha Kaun has been diagnosed with a herniated disc in his back, the Cleveland Plain Dealer reports.

Kaun, a second-round draft pick of the Cleveland Cavaliers in 2008, had a promising rookie season with CSKA Moscow, one of the top teams in Europe.

He was slated to be part of the Russian National Team in the European Championships in Poland, but was unable to play because of the back injury. Doctors have advised him to rest, the Plain Dealer reports.

Beasley to leave rehab

Houston — Michael Beasley Sr. said Saturday that his son is scheduled to leave a Houston rehab center today and expects the Miami Heat to experience a more mature player upon the second-year forward’s return to the practice court.

“He said he learned a lot about himself in this process,” the elder Beasley said by phone, “and it was a wake-up call for him that he needs to take his career more seriously.”

TENNIS

Spain defeats Israel

Torre Pachecho, Spain — Defending champion Spain advanced to the Davis Cup finals by defeating Israel 3-0 on Saturday. Feliciano Lopez and Tommy Robredo beat Jonathan Erlich and Andy Ram, 7-6 (6), 6-7 (7), 6-4, 6-2. Spain will play the Czech Republic in the December final. The Czechs beat Croatia 3-0 in the other semifinal.