Pacquiao said he was "100 per cent" confident he had won the 12-round fight at the MGM Grand and, like his American challenger Bradley, eagerly looked forward to a rematch on Nov. 10 at a venue yet to be decided.
"I didn't listen to the announcement because I thought I had won (verdicts from) all the judges," Filipino southpaw Pacquiao said after ending an unbeaten run of 15 bouts.
"I respect the decision but 100 per cent I believe I won the fight. I don't even remember if he hurt me one punch. He got me with a couple of jabs but I don't remember if he hit me a solid punch in my face.
"I give Bradley credit, maybe three rounds for him because in some rounds I relax. Aside from three rounds, every round I hurt him."
Pacquiao surrendered his WBO welterweight title after earning one verdict from judge Jerry Roth (115-113) while CJ Ross (115-113) and Duane Ford (115-113) gave the fight to the American.
The Filipino's trainer, Freddie Roach, was dumbfounded by the decision.
"I was very surprised they gave it so close," the bespectacled Roach said. "I had it for Manny by 10 rounds to two."
Even Bradley sounded surprised at the decision.
"Pacquiao was a tough, tough warrior. This guy can punch, he has speed. He has all the tools," he said.
"I used my ability to clear some rounds, maybe the last five rounds I feel, to get the victory. I am still shocked."
While Pacquiao said he wanted to respect Bradley after a result which was roundly booed by the crowd, he promised to beat the American inside the distance when they next met.
"It will make me a warrior in having this kind of rematch," Pacquiao said, looking to avenge the loss. "I want to finish him before the whole 12 rounds. I want the rematch."
Bradley, a 5-1 underdog against Pacquiao, was also itching to have the rematch, which he had arrogantly promoted during the build-up to Saturday's fight.
"That was all my idea, pretty much," said the 28-year-old from Palm Springs in California after improving his career record to 29-0 with 12 knockouts.
"Just part of promoting the fight, hyping it up," he added, addressing reporters from a wheelchair.
"I felt I was going to win this fight so the rematch is in place, the date is there. It's definitely going to be a different fight."
Bradley conceded that hearing the boos from the crowd after the decision had been announced gave him added motivation to get back into the ring with Pacquiao.
"I'm happy to be the new welterweight champion but I definitely would like to do this again," said the American, who was back in the ring for the first time since he retained his WBO junior welterweight title by stopping Cuba's Joel Casamayor in November.
"I heard all the boos at the end of the fight, which is okay because we need to do this again. Let's make this more decisive."
Bradley spoke to the media while sitting in a wheelchair before being taken to hospital to have a check on his ankles, which he said he had twisted during the second round.
"I injured my left foot in the second round, twisted my ankle, and now both of my ankles are swollen," he added. "I got hit with some big shots early on but I persevered and went through the pain."