"I was saying to myself, 'Wow, I can't get away from his punches!'" Girard told Business Insider.
Girard had taken the fight on relatively short notice and wasn't in proper shape, something he blames himself for.
Boxing promoter Bob Arum, Girard says, had seen Girard fight and liked his aggressive style - he would be a good opponent for the young, up-and-coming Mayweather.
"He was super fast. His hands were really quick," Girard said of Mayweather. "My style was make him miss, make him pay. This dude, he kept hitting where I couldn't believe it."
Girard faced Mayweather on February 28, 1998, in Atlantic, City, NJ. According to BoxRec, it was Mayweather's 14th professional bout and Girard's 23rd. If you're familiar with Mayweather's record, you know the fight didn't end well for Girard - Mayweather won by knockout in the second round.
As Girard said, he was stunned by Mayweather's speed and accuracy. Mayweather wasn't a big puncher, Girard said, but the accuracy and repeated blows eventually took their toll. In the second round, Mayweather caught Girard in the face, breaking Girard's nose for the first time in his fighting career.
Still, Girard says he had the proper game plan, putting pressure on Mayweather, and that he knows at one point he hurt Mayweather.
"I hit him with a nice right hand on top of the head as he was back into the ropes," said Girard, adding, "I could hear him make that noise, and I knew I had him in trouble. I tried to get him out, but I couldn't finish him."
Girard's account appears accurate. In the second round, Girard hit Mayweather with a big right hand, and the two exchanged a rapid fire of shots (5:35 mark of the video below). However, Mayweather slipped out, unscathed, and later knocked Girard down for a second time in the round, ending the fight.
Today, Girard works at an autobody shop in Providence, Rhode Island (where he also grew up), as he did when he was a professional fighter. According to BoxRec, he fought just two more fights after Mayweather. He says he later quit fighting altogether due to a dispute with his management team. He was tired of working two jobs and training hard and a disagreement with his managers over pay ended his desire to continue.
Girard, however, still loves boxing and continues to watch amateur fights in Rhode Island. He doesn't consider Mayweather the best boxer ever, but holds him in high regard.
"A lot of my friends say he runs too much. He plays defense too much, I guess," Girard said. "Me, my opinion of him, he's a good fighter. That's the name of the game. You ain't supposed to get hit, you're not supposed to let guys hit you. The name of the game is hit and not get hit. And he does it real well."
Girard believes that Mayweather's style has changed. As a lightweight, he was aggressive and came right at his opponents. As he's gone up in weightclasses (he last fought at welterweight), he's backed off a bit. Girard said he heard that Mayweather's hands often hurt, a result of millions of punches over several decades, and perhaps a reason for Mayweather's defensive style.
Still, 19 years later, even with a pair of allegedly bad hands, Girard tilts the upcoming fight with Conor McGregor in Mayweather's favor.
"McGregor is gonna get smashed," Girard said. "McGregor's making his pro debut in boxing, you think he's gonna beat a world champion like Mayweather? No way."
However, if he were in McGregor's corner, he would give the same advice he got 19 years ago - go after him.
"What I would tell him, you gotta pull a Sam Girard. What I did to him - put the pressure on him, no backing up, and get him up against the ropes," he said.
"I could have easily beat him," Girard added. "Because I sparred with him over 100 rounds and in the gym, I was taking it to him almost every time we got in the ring. But I wasn't in shape. That was my fault."