You can consider the fact Moyer, 49, has faced 22-year-old Giancarlo Stanton as well as Hall of Famer Tony Perez.
Perez, a Miami special assistant, turned 70 on May 14.
Manager Ozzie Guillen was 4-for-22 in his career against Moyer.
"When Tony told me he faced him, I don't think Jamie Moyer is 50," Guillen joked. "I think he's like 58. If Perez faced him, come on, wow! You better check his birth certificate."
Actually, Moyer turns 50 on Nov. 18.
Perez was hitless in three at-bats while facing Moyer in 1986.
"I don't remember. He was a rookie," said Perez, who was 0-for-3 in those encounters.
"I never want to hit a young kid," Perez joked. "He was just coming in, and I wanted him to stick around. You see, I made him stick around. Facing a guy who is almost 50, it doesn't make me feel any younger. Right now, with the way he throws, I feel like I can face him again."
Moyer reached another milestone on Monday when he pitched at Marlins Park, which is now the 50th park the left-hander has played, the most of any Major Leaguer.
Miami special assistant Jeff Conine faced Moyer and was his teammate in Philadelphia in 2006.
"He worked as hard if not harder than everyone else," Conine said. "And he is prepared like no one else. Being a left-handed pitcher, he doesn't have to throw real hard. I'm not completely surprised at what he's doing.
"His work ethic is relentless. He shows up a lot of the young guys. He's ultimately prepared."