MANILA, Philippines - Hall of Fame trainer Freddie Roach was unhappy with the performance of referee Joe Cooper during Amir Khan's title defense against Lamont Peterson in Washington DC last Saturday (Sunday in Manila).

Cooper docked Khan two points during the bout, one in the 7th and then in the 12th and final round. The point deductions proved to be vital as Khan lost a contested split decision. Two judges gave Peterson the bout 113-112, while the last gave the fight to Khan, 115-110.

"There was no explanation. He did a terrible job," Roach told RingTV.com. "Referees shouldn't decide fights. He's not a judge. He made himself a judge tonight... The thing is, he decided the fight, not the judges."

"He took two points away for nothing and didn't give warnings," he added.

Peterson is now the new International Boxing Federation and World Boxing Association light-welterweight champion.

Roach also slammed Cooper for missing a "clear" knockdown call. Khan stunned Peterson at the start of the first round, knocking him into Cooper.

Although Peterson went down, Cooper ruled it a slip. Later in the round, Khan floored Peterson again with a right-left combination.

"The first knockdown was clearer than the second one, if you call the second one a knockdown," Roach said.

Roach said Cooper was like "an amateur referee." "A referee at this level of competition shouldn't make those mistakes," he added.

But the five-time Trainer of the Year did give credit to Peterson for his performance, saying the Washington native fought a great fight.

"I don't want to take anything away from Lamont Peterson," Roach said. "He and his team did very well, and I'm happy for him."

"He's a hard worker, obviously, but I want to see them back in the ring one more time," he added.

Both camps have agreed that there should be a rematch, although nothing has been finalized yet.

Roach said that he and Khan formulated a game plan for Peterson, but the challenger was able to apply tremendous pressure, which forced Khan to fight going backwards.

"We'll learn from our mistakes and we'll have to get better," Roach said.

It was Roach's first corner assignment since being inducted to the International Boxing Hall of Fame last week.