Masahiro Tanaka may have rolled the dice by not electing to have surgery in the off season.

TAMPA, Fla. — Even without the filter of a translator, Masahiro Tanaka isn’t much for introspection, so questions about his torn ligament are met with short answers and the thousand-yard stare of someone who’d rather change the subject.

The stoicism makes perfect sense, of course. Tanaka didn’t become one of Japan’s greatest pitchers by worrying about the unknown. Still, he might be the only one in the organization who isn’t sweating. Every conversational road begins and ends with Tanaka’s elbow and how long he can keep pitching without blowing out his UCL.

No one knows, which is why Tanaka is beyond the reach of pitch-by-pitch anxiety. “All I know that I have no pain,” he said Wednesday, repeating an assurance that’s offered up every 24 hours.

Everyone asks — from reporters, to the coaching and medical staffs, all the way up to manager Joe Girardi and GM Brian Cashman. There are a million reasons to think Tanaka is living on borrowed time, but that hasn’t stopped him from gradually increasing his arm speed in camp and renewing his faith in the split-finger fastball, the very pitch that may have caused his injury.

There’s no medical consensus on that, whether the splitter’s wide grip between the index and middle fingers can traumatize an elbow over time. Yankees pitching coach Larry Rothschild said, “We don’t believe that” and Tanaka himself said, “I really doubt it [the pitch] was a factor.”

But plenty of smart baseball people feel differently, including Ron Darling, who was heavily reliant on the splitter back in the 1980s. The right-hander spent an entire summer in the minors jamming a softball between his second and third fingers; that’s how important it was to stretch out his hand before the call-up to the Mets in 1983.

But Darling eventually paid the price, losing his fastball at age 28 and living in so much pain today he plays golf left-handed.

“Just spread your first two fingers as wide as you can and you can feel the flexor muscle in your forearm react,” Darling told the Daily News recently. “Now imagine shoving a baseball between those fingers and throwing it as hard as you can, and you get a sense of strain it causes.”

Darling had this to say about Tanaka, specifically: His splitter is the game’s best since Mike Scott’s in 1986. And putting off Tommy John surgery is a “gamble.”

The good news, though, is in the MRIs taken over the winter. They showed no additional rupture, which means months of rehab, including plasma-rich platelet shots and anti-inflammatory medication, have worked. Tanaka’s arm is exactly as it was last summer, minus the pain.

“When I first injured it, it felt bad enough that I knew I couldn’t pitch every fifth day anymore,” he said. Now, however, Tanaka is working alongside the rest of the Yankees’ hurlers, doing the same drills, preparing to take the ball on opening day.

To say the Yankees need Tanaka to stay healthy is only the G-rated version of their dependency. Without him, they’re looking squarely at the possibility of a 90-loss season. The Bombers don’t have a single starter who they can count on for 200 effective, injury-free innings. Life without Tanaka is too dark a thought for team officials to contemplate.

That’s why Girardi chooses to see his ace through the brightest possible prism. “He’s looked great so far, he hasn’t been holding back at all,” the manager said.

There’s plenty to like about a pain-free Tanaka, given his 12-3 start last year, including a 2.27 ERA, 130 strikeouts and only 18 walks. Opposing hitters weren’t just uncomfortable against Tanaka’s splitters, they were overwhelmed by the fierce, late break. That’s because of how hard he threw the pitch and how much arm speed he was able to generate.

So what happens when it’s time for Tanaka to reach back for one of those monster splitters in April — say, against David Ortiz in a jam? It’s one thing for Tanaka to excel in a controlled environment in camp, or even during the exhibition season when nothing matters. But let’s wait until Tanaka’s adrenaline surges and he’s suddenly amping up that splitter at 90 mph. That’s when the clock starts ticking for real.

Hand on his heart, Tanaka says he is unafraid of living with that partial tear, even if a tough guy like Matt Harvey, who had a similar small rupture in 2013, admitted he couldn’t bear the uncertainty.

The Mets’ ace kept imagining blowing out his elbow with every start, which is why he finally surrendered to reconstructive surgery. Tanaka says, “that’s not my choice,” as he soldiers on.

Brave man. But Tanaka is also smart enough to know rehab hasn’t exactly repaired his elbow. The areas surrounding the tear are stronger, but the rupture itself remains. Only surgery can guarantee Tanaka 100 percent stability in his elbow, if not complete peace of mind.

Not that Tanaka would ever cop to a moment of doubt. He’s ready for war, baseball jammed deeply between his fingers, deferring to the fates. They’ll decide what comes next.