R.A. Dickey exits the New York Mets’ Pentagon City hotel, jaywalks across South Hayes Street and makes his way underground to the Metro platform. “This thing,” he grumbles, stepping gingerly down the broken escalator, “is never working.” He’s not in a bad mood, per se — just a serious one.

It is Tuesday afternoon, and Dickey, 37, is headed to a therapy session — relationship therapy. Dickey and his knuckleball, they are making great progress these days, their understanding of each other growing deeper and richer. But the work must never stop, lest they drift apart again. Later that afternoon, in the bullpen at Nationals Park, they will take their places and pick up where they left off last time.

“It’s definitely a relationship,” Dickey, who carries the best record in the National League (8-1) into Thursday’s start against the Nationals, says before throwing his standard, between-starts bullpen session. “Sometimes we fight. There will be times where I’m yelling at the baseball — like, ‘Do I really know you?’

“That’s what keeps me invested. [The knuckleball] can grow. It’s not just an inanimate thing. It’s very much a living thing. It’s very organic.”

The relationship between Dickey and his knuckleball wasn’t always at this lofty place, with Dickey holding a 2.69 earned run average roughly a third of the way through the season. Theirs was an arranged marriage — forced upon them seven years ago by the management of the Texas Rangers, who noted Dickey’s expanding ERA and declining velocity, and suggested, in no uncertain terms, that for the sake of his own career he reinvent himself as a knuckleballer.

“It’s important to be honest about what you’re not good at,” Dickey says. “When the Rangers came to me and said, ‘We don’t think you can do it anymore as a conventional pitcher,’ there were 29 other teams out there that I could have taken my chances with. But I identified in myself that I wasn’t good enough, I was very mediocre. . . .I like truth. I’m drawn to it in an effort to grow as a person. A big part of that is self-awareness.

“The flight of the pitch is the perfect metaphor for my life anyway — the ups and downs, the grappling with it, the chaos of it.”

A belief in redemption

Dickey is, without question, the Most Interesting Man in Baseball. It isn’t just that he speaks of his primary pitch as if it were a living, breathing thing, or of his development of that pitch as a relationship — but it is partly that. He is the only knuckleball pitcher left in the majors, and only a knuckleballer would speak in such a way.

But he is also a voracious reader of Big, Important Books (for example, “My Name is Asher Lev,” by Chaim Potok; “Life of Pi,” by Yann Martel), a former English major at the University of Tennessee, a born-again Christian and an avid bicyclist. This past winter, he climbed Mount Kilimanjaro in Tanzania — despite the Mets threatening to void his contract if anything happened to him — telling New York magazine, “The scope of the mountain resonated with me.”

He is also a medical marvel, possessing no ulnar collateral ligament in his throwing elbow, which first came to light after the Rangers drafted him in 1996 — doctors concluded either he was born without it, or it disintegrated during his youth — and which cost him a small fortune, since the Rangers lowered their signing-bonus offer from $810,000 to $75,000 upon discovering the missing ligament.

And this spring, he became an author, releasing an autobiography, “Wherever I Wind Up: My Quest For Truth, Authenticity and the Perfect Knuckleball,” that one reviewer called the “best non-fiction baseball book since Jim Bouton’s ‘Ball Four.’ ”

Most media accounts of Dickey’s book focused on its salacious revelations — the multiple episodes of sexual abuse that Dickey suffered as an 8-year-old; the marital infidelity Dickey inflicted upon his wife, Anne (with whom he remains married, with four kids); and his discovery of a syringe on the Rangers’ clubhouse floor in 2001.

“I certainly believe in redemption,” Dickey says of his decision to be so forthcoming in the book. “Hope and redemption go hand in hand, but in order to get to redemption you have to walk through quite a bit of darkness, and for me, being honest about a past that was difficult and dark is part of the process of becoming fully me.”

But at its core, the book is a tale of twin journeys, those of his professional life and his personal life, that both reached tipping points when he was in his early 30s — and that, as Dickey discovered, were not actually separate journeys, but facets of the same one.

“Do you think that it’s a coincidence that when I was finally able to stop hiding as a human being, I also stopped hiding as a pitcher?” Dickey wrote. “I don’t.”

A chance to explore

The Most Interesting Man in Baseball steps off his Yellow Line train at the L’Enfant Plaza Metro stop, walks across the overpass and climbs down to the platform to catch the Green Line to the Navy Yard/Nationals Park stop. Not one person appears to recognize him during the approximately 20-minute ride from the team hotel to the stadium.

Dickey is a connoisseur of urban subway systems, riding them in any road city where there’s a stop at the ballpark, and at even at home in New York. “New York’s subway system,” he marvels, “is the eighth wonder of the world.”

He mentions the San Francisco Bay Area, Atlanta, Chicago and Washington among his favorite subway systems on the road, although nothing, he said, compares to the old Canadian cities of the Pacific Coast League — Calgary, Edmonton and Vancouver, none of which remain in the PCL.

“Calgary, now that was an awesome subway system,” he says. “You’d ride to the stadium, get a table at an outdoor cafe downtown, and ride back to your hotel.”

Dickey values both the opportunity to explore a city the way the locals get around, and the element of adventure it brings. He has gotten lost more than once. One time, in Washington, he switched to the wrong train, ascended to the street level to get his bearings and found himself outside of the U.S. Holocaust Memorial Museum. Realizing he had a little time to kill before he needed to be at the ballpark, he went inside.

“I have,” he says, “a very devout interest in growth.”

Though he has been in professional baseball for 16 years, and first broke into the majors 11 years ago, it was only in 2010, his first season with the Mets, that Dickey established himself as a solid, dependable, effective big league starting pitcher. First, he had to straighten out his life, and crooked-out his pitches.

Around the same time he made the switch from conventional pitcher to knuckleballer, he began seeing a psychotherapist, Stephen James, in his native Nashville — and eventually revealed to him the scars from his past.

“I hated myself. I really did,” Dickey says. “It was hard to look in he mirror. I was tired of projecting out one person while inside I was somebody totally different. And I got to a point of real brokenness with that. That’s when I was introduced to Stephen in Nashville, and he talked to me about a different way to live, and I embraced that.

“When I was presented with a different way to live, it’s almost like I’d been waiting on it my whole life. I was 31, 32 years old when I really got started, when my growth really began for me. I’ve grown more in the last six years than I did my previous 30.”

A limited fraternity

Meantime, Dickey plowed forward with the switch to the knuckleball, first with the Rangers organization — his first and only big league start for them as a knuckleballer, in 2006, was a disaster, as he gave up a record-tying six home runs — then with the Seattle Mariners and Minnesota Twins.

Former Rangers knuckleball ace Charlie Hough worked with him extensively, showing him a new grip and a repeatable delivery, and he later got lessons from noted knuckleballers Phil Niekro and Tim Wakefield. The small cadre of knuckleball specialists acted very much as a fraternity.

“There’s an instant bond because we’re the only ones who have walked a mile in each other’s shoes,” Dickey says. “I used what they gave me and infused the pitch with my own personality.”

Dickey’s knuckler is different from others in that it is harder — typically in the mid- to high-70s, as opposed to the mid- to upper-60s. As a result, he is able to keep it in the strike zone with consistency unmatched for a knuckleballer, while still fooling hitters with its flutters.

“He’s got the rising one, the sinking one, the sideways one — it’s tough to hit,” says Nationals slugger Michael Morse. “You see it, and by the time you swing it’s in another spot. Squaring up his knuckleball is tough. You basically have to go up there and take all your mechanics and everything you’ve learned, and throw it out the window, and just kind of go Little League — just swing as hard as you can and hope you make contact.”

Most of Dickey’s rate statistics through his first 11 starts of 2012 are running at career highs — including his walk rate (2.1 per nine innings) and his strikeout rate (8.6 per nine innings) — and he is positioned, with another month’s worth of solid performance, to make his first all-star team.

“That would be nice,” he says. “It would be recognition that what you do is legitimate, and just because you throw a knuckleball doesn’t mean you can’t be just as valuable as the 100-mile-per-hour-fastball guy.”

Everyone thinks the 100-mph-fastball guy has it all over the knuckleball guy, but Dickey knows better.

The fastball isn’t a living thing; it’s a rock in a slingshot, a bullet. They don’t have a relationship; it’s a one-way street. The fastball guy may love his fastball, but without that shared history, without the trust built up through understanding each other’s needs, it will never love him back.