Then Monzon swung and missed badly at the next two pitches, becoming one of Clemens' club-record 11 strikeout victims.
"In my first at-bat, I wanted to see all of his stuff," Monzon said. "So he threw me a fastball that I thought was right in the middle, and it wasn't. It was outside. I would say that's the first fastball I've seen that cut so much."
Monzon got the best of Clemens in his second at-bat in the fifth, however. After taking a couple of pitches, the 24-year-old slapped a single over second baseman Johnny Ash's head.
"I was just thinking, 'Is that going to drop?'" Monzon said.
It did, landing for San Antonio's first hit and breaking up The Rocket's perfect game after 4 1/3 innings.
"Somebody in the stands told me, 'Hey, finally somebody got a hit. And did you know he's double your age?'" Monzon said. "That's awesome. He's a Hall of Famer. I don't know if I've ever seen someone with a splitter like that."
Luis Oliveros can't recall a splitter quite like The Rocket's, either. Oliveros struck out rather quickly in his first at-bat -- going down on three pitches in the third.
But Oliveros took what he learned in that plate appearance and applied it to his second. It worked.
"I got a hit off Roger Clemens," Oliveros boasted.
Yeah, he did. Oliveros lined a single to center field in the sixth for San Antonio's second hit, despite falling behind, 0-2, against the 43-year-old right-hander.
"There's not too many guys that can throw with Roger's speed," Oliveros said. "He's speedy, he's a dominator, he's everything."
Monzon agreed. He'd faced pitchers like Russ Ortiz, Aaron Sele and Trevor Hoffman during their rehab appearances and in Spring Training. But they don't compare to Clemens -- even at his age.
After Monzon's hit, he gave Clemens a test on the basepaths.
"Our [first-base] coach [Henry Cotto] kept asking me if I had the green light," Monzon said. "I was like, 'Do I?'"
He did. San Antonio manager Daren Brown gave Monzon the green light, and he took off for second midway through Wladimir Balentien's at-bat. He made it safely.
"He was going high kick every time, high kick, high kick," Monzon said. "I'm an average speed guy. I don't steal a lot."
Yet he stole one off Clemens, who allowed just two hits over six innings. Still, Monzon has to debate which means more: the single or that stolen base.
"Both," he said jokingly.
For Oliveros, he only has one baseball moment that ranks above his single off Clemens.
"The better moment I had besides that one is when I signed my first professional contract," Oliveros said. "That was an exciting moment. That's it. It was quite a day because everybody knows Clemens."
Now, thanks to The Rocket, a few more people know about Oliveros and Monzon.