Manny Pacquiao's closest boxing confidant, trainer Freddie Roach, admitted he hoped to see the Filipino fight on.

The Filpino superstar announced his retirement after winning a twelve round unanimous decision over Timothy Bradley on Saturday night at the MGM Grand in Las Vegas.

"I would like to see him fight again, yes," said Roach, while stressing he would back Pacquiao whatever he decided. We've had a great 15 years together. If he retires, I'll be happy for him. That's kind of up to him," Roach said.

"I know he's in physical shape to keep fighting – his speed is good, his legs are good, his work ethic is great.

"He could continue to fight on, but if he retires and spends more time with his family and he enjoys life, and has something to fall back on, then I'll be 100 percent behind him."

While boxing history is littered with fighters who have fought on for too long – with often calamitous results – Roach wondered whether Pacquiao in fact would be haunted by regret if he left too soon.

"You know, it's a difficult sport to quit, it's really,really hard to retire and I think he hasn't realised that yet. But he will soon," Roach said.

Pacquiao's masterclass in ringcraft on Saturday merely confirmed the trainer's suspicion that he was capable of extending his career.

"We talked about it being his last pro fight and I said 'Go out with a bang, let's look good doing it.' And he did that," Roach said.

"I thought at moments tonight he looked better than he has done in a really long time. When I see Manny aggressive like that – that's the best Manny Pacquiao.

"I saw him smiling quite a lot in the ring tonight and that just tells me how much he loves the sport."