Timothy Bradley: No Rounds Off, I Need To Win Each One

Timothy Bradley once fought in lumberjack yards, on the weekend he'll battle Manny Pacquiao - considered one of the world's best pound-for-pound fighters.

Timothy Bradley says he is not about to let the chance of a lifetime pass him by when he steps into the ring against Filipino fight king Manny Pacquiao on Saturday.

"It's all or nothing," Bradley vowed. "No rounds off. Round by round, I have to win each one."

Bradley, 28, is unbeaten in 28 fights. But he has never fought anyone of Pacquiao's stature and his record includes just 12 knockouts.

He'll be fighting for just the second time at 147 pounds, moving up to challenge for Pacquiao's World Boxing Organisation welterweight belt.

Pacquiao's trainer Freddie Roach says he doesn't believe Bradley has the speed or power to beat his fighter.

Roach questions the wisdom of Bradley's vegan diet - a rarity in the boxing world - and says the Californian's muscular physique could be a hindrance rather than an asset.

Bradley acknowledges the highly publicised bout is a step up for him, but says the years of paying his dues fighting in club venues have given him the versatility to adapt to whatever Pacquiao presents.

"I came from the lumberjack yards, fighting in little ballrooms. Now we're in Las Vegas ... and we're going to be fighting in front of thousands of people," said Bradley, who once waited tables to support himself as he tried to establish his ring career.

"It's been a long journey, but I knew at some point I would get here."

In 2008, Bradley travelled to Nottingham, England, where he defeated Junior Witter to win the World Boxing Council light welterweight world title.

He said he took home about $US40,000 for that bout -- a useful payday for a man who had just a few dollars in the bank at the time.

On Saturday he stands to make a minimum of $US5 million, but a victory over Pacquiao -- regarded by many in the sport as the world's best pound-for-pound fighter -- would be a priceless boost to his career.

Bradley says he will do whatever it takes to make that happen.

"I don't look pretty, I don't look spectacular. I don't have that spark. I don't do that one thing where everyone says 'Wow'," Bradley admitted.

"I know I'm going to have to do it in this fight. You could see some greatness on Saturday."