Today is a glorious day. The Mets have done themselves, their city, and their game proud. Rickey Henderson — the greatest — is finally back in the majors, the newest addition to the Mets’ coaching staff.

A few years ago, legend has it, San Diego Padres general manager Kevin Towers found the following message on his voice mail: “This is Rickey calling on behalf of Rickey. Rickey wants to play baseball.” At the time, Rickey was 43 and still better than quite a few players in the majors. Towers demurred, Rickey moved on to the Boston Red Sox and put up a .369 on base average in 72 games, and the Padres lost 96 games.

There are a thousand Rickey Henderson stories, and I would like to believe that every single one of them is true, from the time he supposedly framed a check for a million dollars without bothering to cash it, to his supposed response when Tony Gwynn told him he could take any seat he’d like on the team bus, on account of his tenure. (“Ten? Rickey got 20 years in the big leagues!”) They probably are all true. Why wouldn’t they be? What’s stranger, after all — the idea of Rickey standing naked in front of a mirror before every game declaiming, “Rickey’s the best!” or the idea of a 47-year-old ballplayer, one of the 10 or 15 best of all time, playing for the San Diego Surf Dawgs?

Some people have always thought of Rickey as an egoist, a man-child, or a malingerer. I say the man is a genius and must be allowed his idiosyncrasies. He was the absolute best at what he did, which was play baseball. Forget about the stolen bases; the man broke Ty Cobb’s career record for walks and Babe Ruth’s career record for runs, in each case doing something vastly more impressive than what Pete Rose did when he broke Cobb’s hits record. He’s a national treasure, someone to be treated with the greatest reverence, our own Mays or Aaron. He may have sat out the odd game in his day when his hamstrings were tight. He also played in the majors until he was 44.

If you had made me general manager of the Mets two days ago, my first move would have been to sign Rickey Henderson, and I would have put him in left field. The team is still shorthanded out there, and I’ll bet Rickey is still good for a .350 on base average and the odd stolen base; his time may yet come. If it doesn’t, though, the Mets have still made a brilliant move in signing him up as a coach.

One reason for this is that Rikkey is not merely a holder of several of the most important and impressive records in the history of American sport, and not merely a character who single-handedly shames and mocks the endless number of dreary, joyless robots masquerading as ballplayers who speak with all the passion and sincerity of network news anchors. He is, again, a genius on the field. There are probably several dozen players in organized baseball right now who are faster than Henderson was in his prime. He stole all those bases and scored all those runs and played all those years not because of his body, but because of his brain.

Rickey could tell from the faintest, most undetectable twitch of a pitcher’s muscles whether he was going home or throwing over to first. He understood that conditioning isn’t about strength, but about flexibility. And more than anyone else in the history of the game, heunderstoodthatbaseball is entirely a game of discipline — the discipline to work endless 1–1 counts your way, the discipline to understand that your job is to get on base, and the discipline to understand that the season is more important than the game, and a career more important than the season. Maybe he’d get a bit more credit for all this if he were some boring drip like Cal Ripken Jr., blathering on endlessly about humility and apple pie and tradition and whatever else, but we’re all better off with things the way they are.

Even more important, though, is that Rickey has retained every bit of his passion for the game. He was not playing for the Newark Bears and the San Diego Surf Dawgs because he needed the money; the man simply doesn’t want to do anything other than play and teach baseball. Four years ago, Baseball Prospectus asked him if he’d like to be a manager one day, and he said, in part, “I could be a first base coach. I’d have some great knowledge to share doing that. Show them what to do, work on reading pitchers and timing on those guys. Is there anyone you’d want more than me over there?”

Absolutely not. When you watch Jose Reyes blossoming into the best player in the league, someone who will likely end up drawing three times as many walks this year as he did two years ago, you’re watching something in which Rickey had a hand. As a spring training instructor the last two years, Rickey has had a single job: To teach Reyes how to stay healthy, how to play with discipline, how to read pitchers on the bases and at the plate. Reyes, not Rickey, gets and deserves the credit for his astonishing growth, but the thought of what Rikkey might do to help Carlos Gomez and Lastings Milledge simply makes the mind reel.

While all of this is great for the Mets, though, best of all is that the game is simply brighter, more joyous, and more tightly anchored to the best of its past with Rickey in it. Everyone had their fun when he broke Lou Brock’s stolen base record and proclaimed, “I am the greatest,” but he was, of course, just saying what was plainly true. I wish every ballplayer had half his talent, passion, and brains, and took half the delight in the game that he does. To anyone who loves the game, Rickey is the king, and with him in a major league uniform, he’s back on his throne.

tmarchman@nysun.com