The 49-year-old Moyer allowed six hits in seven innings to earn the win in the Rockies' 5-3 victory over the Padres on April 17, his third start this season.
At 49 years and 151 days, Moyer surpassed the previous record held by the Brooklyn Dodgers' Jack Quinn, who beat the St. Louis Cardinals at Ebbets Field on Sept. 13, 1932, at 49 years and 70 days old. Moyer also tied Hall of Famer Jim Palmer for 35th place on the all-time wins list with 268.
In three starts this season, Moyer is 1-2 with a 2.55 ERA over 17 2/3 innings.
Pirates manager Clint Hurdle marvels at what Moyer is doing.
"It's a story that only sport can come up with, the fact that he's been able to make the club, No. 1, and to win a game, No. 2, and now we're going to get to see him and he's going to battle and he's going to compete," Hurdle said.
Though Pittsburgh has been anemic at the plate -- the Pirates enter Monday's opener with a team batting average of .203, the worst in the Majors -- the club has remained competitive thanks to a pitching staff that ranks third in the National League in ERA (2.53).
Pittsburgh hasn't scored or given up more than five runs in a game this season, the longest such streak to start a year in the NL since the 1965 Pirates.
That team shook off a 6-10 start to finish 90-72 and featured three Hall of Famers in Roberto Clemente, Willie Stargell and Bill Mazeroski.
Rockies: Aggressive baserunning paying dividends
The Rockies have 14 stolen bases in 14 games, and manager Jim Tracy said that aggressiveness while running the bases has become an extra weapon for his team.
"There are situations where we force the action from in here in the dugout, and there have been other instances where some of our players have been on their own and made very, very good decisions in picking pitches to run on," Tracy said.
Pirates: Correia to get start
Kevin Correia (1-0, 1.50 ERA), who was scratched from his scheduled start on Saturday due to pain in his side, will get the nod in place of Brad Lincoln.
The Rockies, who just took two out of three from the Brewers, won't face Milwaukee again until a three-game set at Coors Field on Aug. 13-15.