By Thursday night, the Mets and the Subway Series will be part of Mariano Rivera’s glorious past.

Baseball’s all-time saves leader, with 626, was in his first season as the Yankees’ closer when interleague play started in 1997.

Now, the 43-year-old Rivera is still closing and is 18-for-18 this season after missing five months last year due to major knee surgery.

Tomorrow night at Citi Field, the Mets will honor Rivera before the game.

“I will make sure I say thanks,’’ said Rivera, who will meet with a group of baseball fans at Citi Field as he has done this season on the road. “They go out of their way to honor me. I respect that and I am grateful. I don’t take it for granted. For me, they are not a rival. I do respect them.’’

Rivera’s 20 saves against the Mets is easily his most against a National League team and in 16 regular seasons of Subway Series games, he has more than a few memories.

“Saving two games in one day,’’ said Rivera, who did that on July 8, 2000 at Shea Stadium and Yankee Stadium.

Rivera’s only major league RBI was delivered at Shea when he drew a bases loaded walk and he notched save No. 500.

“We played a lot of games there,’’ Rivera said of Shea.

Like a lot of players on each side of the Subway Series, Rivera believes the fans get more out of games than anybody else.