SAN FRANCISCO – Freddie Roach knew payback was in order as he walked to the podium Saturday, the Golden Gate Bridge gleaming in the sun behind him and Oscar De La Hoya, his former boss and present enemy, staring at him with hard eyes.

A day earlier, at the Space Center in Houston, De La Hoya had gotten the better of his former trainer at the midway point of a week-long trip across America to hype De La Hoya’s Dec. 6 showdown with Roach’s best boxer, Manny Pacquiao. There De La Hoya had told a wild-eyed crowd of his Latino supporters that he knew what Roach would say to Pacquiao at the critical moment of their fight in Las Vegas.

“Houston, we have a problem,’’ De La Hoya said mockingly, using NASA’s infamous phrase of impending disaster as the crowd roared its approval.

Now it was Roach’s chance to respond and he didn’t miss his moment. As he strode to the outdoor podium set up on the Upper Meadow at Fort Mason, he reached into a plastic bag and pulled out a toy machine gun.

“Oscar,’’ Roach said. “I found this toy gun. I can’t pull the trigger. It must be yours.’’

The crowd roared at the veiled reference to Roach’s earlier claim to TSS that De La Hoya could no longer pull the trigger when it was time to throw punches, the many Filipino transplants living in San Francisco who had gathered on the wide lawn cheering loudly while De La Hoya wore a tight, hard smile.

A few minutes later Pacquiao would one up the man he is preparing to challenge as well when he related how the two had just come from a similar press conference to hype the fight’s pay-per-view sales. There De La Hoya had referred to a historic moment in American and Mexican history to try and deliver a threat Pacquiao. As it turns out, it had been a waste of breath.

“Yesterday we went to San Antonio and Oscar said, ‘Remember the Alamo!’’’ Pacquiao said wryly. “But you know what? I don’t know what is the story of the Alamo in San Antonio.’’

As the crowd cheered even De La Hoya broke into wild laughter, finally putting his head down on the dais to try and compose himself. It was an odd series of moments because here were two guys promising in every city they visited to all but decapitate each other in two short months yet everyone seemed to be in high spirits. Historically, that has not often been the case when these week-long, cross country jaunts are made to hype a major fight because usually as the end nears the combatants can barely stand the sight of each other.

That’s what happened when De La Hoya made a 13-city, seven-day trip from L.A. to New York with an arrogant Julio Cesar Chavez in 1996 to pump up interest in their first meeting.

It was true when Marvin Hagler did it with Thomas Hearns and when Hearns did it with Ray Leonard and when Hagler did it with Leonard as well. The list goes on and seldom did it not end with the two sides either snapping at each other, disparaging each other or, worse, attacking each other as Mike Tyson did the day he bit Lennox Lewis in the thigh during a melee at the opening of a New York press gathering called to promote their first and only meeting.

“It’s not necessary to push and shove each other, to hate each other,’’ De La Hoya said later. “It’s not necessary with us because with our styles we know we’re going to get a fight. You don’t need to have all that shoving and pushing. Usually when you have that the real fight is a snoozefest.

“I’m 35 years old. At this point I’m having a good time. Don’t get me wrong. I’m training like a madman but we don’t need all that.’’

So instead we get a few jokes, some words of respect and then the inevitable promise by Pacquiao and Roach that the six-inch reach advantage De La Hoya enjoys will not be a factor because it will be trumped by Pacquiao’s youth and superior speed while De La Hoya counters that speed won’t enter into it because Pacquiao will not be able to resist the temptation of meeting him face to face to rumble, young man, rumble.

“Manny will engage with me,’’ De La Hoya said. “We’ll clash. If he hits harder than (former middleweight champion Bernard) Hopkins I’m in trouble. If he can box like Pernell Whitaker or Floyd Mayweather then I’m in trouble.’’

The way De La Hoya made those statements it’s clear he doesn’t believe either is the case. He believes Pacquiao is a dangerous little man in with an equally dangerous bigger man. In this case at least, size matters.

What does not, is pre-fight insults, although apparently no one has yet explained that to De La Hoya’s new trainer (his third in as many fights). Nacho Beristain did not take kindly to what he perceives to be Roach’s disrespecting De La Hoya and he took his younger counterpart to task for it Saturday.

“I’m very disappointed in Freddie Roach,’’ Beristain said. “I consider him a very good trainer but he lost his ethics. To talk about about his ex-boss is not right. Maybe of he can’t pull the trigger it’s because Roach could not exploit his talent?’’

As Beristain’s words in Spanish were translated, Roach appeared to get more than a little agitated at what Beristain had to say. Twice he hollered to him, waving his arm in a dismissive gesture. It was the kind of momentary flare up of emotion one was supposed to see after a week spent too often seeing someone you will soon be trying to punch in the lip.

It was the one moment of flash during a two-hour session that seemed more like a business convention than the launching of a fistic confrontation that is likely to break box office and pay-per-view records. Then again, Dec. 6 will be as much a business convention in Las Vegas as a fistic confrontation because that is what Oscar De La Hoya has become – a businessman who fights when the financial times are right.

As for what Manny Pacquiao will be that night only one things is sure – he’ll be as good a Little Big Man as he can be. Whether that’s good enough to beat a bigger but older and slower six-time world champion may well come down to whether or not the gun De La Hoya brings with him comes equipped with a more functional trigger than the one his former trainer had with him on a sun-drenched hill in San Francisco last weekend.