For the first time since 1994, the Mets held Old-Timers' Day at Citi Field, where some of the team's legends came out of retirement —at least for a day — to play ball.  Credit: Newsday/Heather McGowan, Mike Drazka

It took 50 years, but Joan Payson’s promise to Willie Mays finally was fulfilled.

No Mets player will ever wear his No. 24 again.

Before Saturday’s Old-Timers’ Day game at Citi Field, the Mets announced that they would be retiring Mays’ iconic number during an on-field ceremony.

“We are very pleased that as part of the ceremony today, we can retire Willie Mays’ No. 24,” team president Sandy Alderson said. He was joined by Mays’ son, Michael, and Cleon Jones.

“We kept it as sort of a confidential segment of the ceremony,” Alderson continued. “We wanted it to be a little bit of a surprise. But I think it’s important, at least speaking on behalf of the organization, that we were able to do it on a day like today, which was so momentous and provided a tremendous sort of context for the retirement of the number.”

Mays’ No. 24 is the seventh number retired by the Mets. He joins Gil Hodges (No. 14), Keith Hernandez (No. 17), Mike Piazza (No. 31), Jerry Koosman (No. 36), Casey Stengel (No. 37) and Tom Seaver (No. 41).

Jackie Robinson never played for the Mets, but his No. 42 is retired across all of Major League Baseball.

Alderson explained that the decision to retire Mays’ number had been a consideration “for many months, if not a year or two” by the organization’s Hall of Fame committee.

“It was a very strong feeling among the committee that this was an appropriate retirement,” Alderson said. “And then there was the Steve Cohen factor. And I think Steve, who has become involved with the Hall of Fame — not necessarily as a voting member but somebody who I think has some influence.

“The ultimate determinant was that a promise was made and needs to be fulfilled. And I think that given all of the other considerations, that honestly shouldn’t have been the determining factor. But it was certainly important to Steve.”

When the Mets acquired Mays from San Francisco on May 11, 1972, Payson, the owner at the time, promised the future Hall of Famer the Mets would retire his number.

Mays hit .238 with 14 home runs in 135 games spanning the remainder of the 1972 season and 66 games in 1973. Over the course of his 22 seasons with the Mets and Giants, Mays hit .302 with 660 home runs and drove in 1,903 runs. He was selected to the Hall of Fame in 1979, receiving 94.7% of the vote.

“I saw Hank Aaron. I saw [Roberto] Clemente. I saw all the other guys who were outstanding. This man was just the best that ever played the game,” Jones said. He added, “It’s a pleasure for me to sit here and talk about the greatest player that ever played the game, in my opinion.”

Mays, 91, was not in attendance because he is recuperating from hip replacement surgery, Michael Mays said. The Mets still released a statement in his name.

“I want to thank Steve and Alex Cohen for making this day possible and embracing Mets history,” the statement read. “I can never forget the way it felt to return to New York to play for all the loyal Mets fans. I’m tremendously proud I ended my career in Queens with the Mets during the ’73 World Series. It’s an honor to have my number retired in my two favorite cities — New York and San Francisco. New York was a magical place to play baseball.”

The announcement was a fitting climax to the Mets’ first Old-Timers’ Day since 1994, as 65 players and managers from every era in franchise history were honored. Said Michael Mays: “We’re thrilled.”