Julio Cesar Chavez Jr. retained the WBC middleweight title Saturday night, earning a unanimous decision over fellow Mexican Marco Antonio Rubio.

The judges scored the bout 118-110, 116-112 115-113 for Chavez, which drew a mixed reaction from the 14,120 in attendance Saturday at the Alamodome.

Neither fighter went down despite taking continuous heavy blows to the head and body throughout the 12-round bout.

Chavez (45-0-1-1) overcame a gutsy performance by Rubio (53-6-1) despite having some trouble entering the fight.

Chavez, who hails from Culiacan, struggled to make weight for the championship bout and was arrested on drunken driving charges Jan. 22 in Los Angeles.

"He wasn't as tough as I thought he would be," Chavez said. "I felt good about myself the whole fight. I felt a lot stronger than him. He never hurt me in the fight. I felt his punches, but he never hurt me."

The fighters spent most of the bout standing shoulder to shoulder, which resulted in a couple of head butts and two warnings to Rubio for low blows. Although Chavez won handily on the scorecard, many of the closely contested rounds could have been scored either way.

"He was too heavy for me," Rubio said. "I couldn't handle his weight. It was body to body. It was too much for me to handle."

Chavez landed 237 of 560 punches thrown and Rubio landed 201 of 962.

The boxers exchanged a series of vicious blows in the 11th, with Rubio appearing to daze Chavez with a couple of overhand rights midway through the round. Chavez kept pressing forward despite the blows in the hardest fought round of the bout.

Nonito Donaire dominated the co-main event, winning a 12-round split decision over Wilfredo Vazquez Jr. to win the WBO junior featherweight title.

Donaire (28-1), making his debut in the 122-pound weight class, won 117-110 on two scorecards and lost the third 115-112.

The "Filipino Flash" controlled the bout despite breaking his left hand somewhere between the second and fourth rounds before a crowd of 14,120.

After capturing world titles in the flyweight, super flyweight and bantamweight divisions, Donaire proved just as powerful in moving up to junior featherweight.

Vasquez (21-2-1) went down in the ninth, staggered by a left uppercut before being dropped by a left overhand. Vasquez rose quickly, smiling as the referee came over to give him a standing eight-count.

Donaire also stunned Vazquez in the third with a left-handed uppercut to the right temple.

NOTES: Former world champion Julio Cesar Chavez was at ringside, providing Spanish color commentary for Donaire's bout before watching his son's fight as a spectator. Among those in attendance were former world champions "Sugar" Shane Mosley of Golden Boy Promotions and San Antonio native "Jesse" James Leija.