They became battery mates in 1959, when both were in their first years with the Cardinals. McCarver was 17 years old back then; Gibson, 23. They ended up pairing for nearly 200 games, and while McCarver certainly doesn't remember all of them, more than a few stick out in his mind.
Like Sept. 12, 1959, at Wrigley Field. Gibson was making his 12th appearance, looking for his second win. He would up throwing a complete game in a 6-4 Cardinals win.
"It was the first time he struck out 10 in a game," McCarver said. "It wasn't the last."
McCarver, who retired from his post as a national broadcaster for FOX last year, provided commentary for 30 Cardinals games this year on FOX Sports Midwest, extending a long broadcasting career that began shortly after he retired from playing in 1980.
He and Gibson were Cardinals teammates from 1959-69 and again from 1973-74. They were All-Star teammates twice, in 1966 and '67, and played in three postseasons together, in 1964, '67 and '68.
Monday wasn't the first time the two have taken the field together for a ceremonial first pitch, but it was the first time they'd ever reversed roles. Earlier this season, to celebrate the Cardinals' 1964 World Series win, Gibson threw out the first pitch to McCarver.
This time, McCarver looked forward to switching things up a bit.
"What makes this so interesting," McCarver said, "is that with Bob catching the ball, he's never really seen the park from this view, because he didn't have to back up home that much. The only time you back up home is when a lot of runs score. So, I wanted to introduce him to the ballpark from this view."
Asked if he thought Gibson would be a harsh critic of his first pitch skills, McCarver shook his head no.
"I told him not to wear a cup," McCarver laughed. "I've waited 50 years for this. To do to him what he did to me for 197 starts."
A postseason game in St. Louis wouldn't be complete without a healthy showing from their alumni, and Monday was no exception. The lobby of the Cardinals' clubhouse was a veritable who's who in the minutes leading up to game time at Busch Stadium. Along with Gibson and McCarver, Hall of Famer Lou Brock also was in attendance at Game 3 between the Cardinals and Dodgers.
Following the first pitch, the colors were presented by the Joint Service Color Guard, while the American flag was unfurled by active duty and retired members of all segments of the armed forces.
The anthem was performed by a music group from Scott Air Force Base in Illinois, 4-Digit Chord.
Prior to NLDS Game 4 on Tuesday, former All-Star third baseman Scott Rolen is scheduled to throw out the ceremonial pitch.