LAS VEGAS -- Oscar De La Hoya and Bernard Hopkins both did what they had to do by winning their fights Saturday night at the MGM Grand to set up a highly anticipated Middleweight title bout on September 18.

De La Hoya (37-3) won a questionable unanimous decision over Felix Sturm (20-1) to claim the WBO Middleweight title. Sturm landed 43 percent of his punches compared to 24 percent from De La Hoya, as the former champion seemed to weaken the challenger midway through the fight. All three judges scored the fight 115-113.

"Everything went wrong tonight," an apprehensive De La Hoya said. "What can I do? What can I say?"

Hopkins (44-2-1) got the night started by earning a unanimous decision over a lethargic Robert Allen (36-5), to retain the WBC, WBA and IBF Middleweight crowns. Hopkins won 119-107 on two scorecards and 117-109 on the other.

"I was nervous a bit about what De La Hoya and myself had to do to set up a fight between us in the near future," Hopkins said. "I was nervous, but it won't happen again. Trust me."

The scheduled fight between De La Hoya and Hopkins is expected to have a payout of nearly $10 million.

De La Hoya needed to pick up the intensity and fought furiously in the final two rounds which he failed to do early on.

Sturm, who came into the fight holding the lightly regarded WBO 160-pound title, fought like he was the challenger instead of the champion by being aggressive throughout.

Sturm, who raised his right hand in victory following a fast-paced first round, used that hand to give a heavy dose of jabs to De La Hoya's face throughout the fight. Fighting in his first bout in the United States, the former champion bloodied De La Hoya's nose in the first three minutes and continued to attack the face after that.

"He was young and hungry," said De La Hoya, who was fighting in his sixth different weight class in his career. "He has a wonderful jab and I tried to defend it, but I couldn't."

De La Hoya was making his first fight in the middleweight division after losing his 154-pound title to Shane Mosley last September.

To counter Sturm's jabs, De La Hoya worked his opponent's body to try and wear him down.

Sturm did a solid job at blocking most of De La Hoya's body shots throughout the fight.

Heading into the 11th round, De La Hoya started firing combos on Sturm with some being successful. Sturm seemed to counter the blows in the final two rounds with more jabs, but the judges saw it differently.

The crowd booed unanimously after the fight as Sturm raised his hands in victory. But the those boos quickly turned to cheering as the announcement was made that De La Hoya had earned the decision.

"I know I can do better," said De La Hoya, who had a look of shock on his face after he heard the announcement. "I don't know what happened tonight, but nothing worked."

Sturm also had a shocked look on his face after the announcement was made and didn't go across the ring immediately to congratulate De La Hoya.

"I know he is one of the biggest names in this sport, but I don't believe it," the former champion said. "Everyone that watched this fight tonight knew that I was the better fighter and that I won."

Hopkins watched the entire fight from his locker room and cameras showed a nervous expression on his face as the fight moved into the later rounds.

"My blood pressure was rising throughout the fight," Hopkins said after De La Hoya's fight. "I couldn't take it. But the judges did a great job in Oscar's fight and we will now get the chance to battle it out."

Hopkins got things started by winning an easy fight over Allen. The challenger posed no threat throughout the contest.

The defending champion knocked Allen down 45 seconds into the seventh round with a strong right. Allen was down until the count of five before he got back up to his feet. He was on the canvas four different times throughout the bout, as he slipped twice and fell once after missing with a left.

"I had him hurt throughout the fight, but I wanted to be careful because he can hit and I didn't want to get caught off guard," Hopkins said. "I got loose after I popped him a couple of times and I settled into a groove."