DETROIT — Jose Valverde does not understand the infatuation with his split-finger fastball.

He got over his infatuation with it years ago.

Still, it’s the daily question he has to answer.

Where did it go? When is it coming back? How often will he use it?

Wednesday the Tigers’ closer got a bit irked by the continual line of questioning about the supposedly Missing In Action pitch, which he has admittedly thrown infrequently since returning to the team.

“Right now, I don’t need to throw my split-finger every pitch, because I have a lot more pitches,” he tried to patiently explain. “When I play in Arizona, I had to throw my split and my fastball a lot, because I don’t throw sinker. Right now, so far I throw sinker and (four-seam fastball).”

According to Fangraphs’ compilation of PITCHf/x data, he’s thrown the splitter 6.5 percent of the time. Out of 103 pitches thrown in his first seven appearances, only seven have been split-finger fastballs.

Three of them were doozies he uncorked in Tuesday night’s ninth inning, two of them pitches that the Astros’ Chris Carter and Carlos Pena took for called third strikes.

“Last night, he threw a couple splitters, and we were tickled about that. Two of them were pretty darned good, and the other one was just OK. But that’s good,” manager Jim Leyland said.

“On Sunday, against Cleveland, because it was cold, he just couldn’t feel it. Just couldn’t feel it with his fingers, that’s why he didn’t throw it.”

In all the discussions of where, when, why and how soon, that’s been the one common denominator, the one reason given for the lack of usage of the pitch: Cold weather. Psychologically, you tend to shy away from a pitch when you know conditions won’t allow you to throw it properly.

“Once the weather warms up, I don’t think that’ll be a factor. But I think in cold weather, when you don’t get a feel for it, yeah. It’s a tricky pitch to throw. It’s not an easy pitch to throw. And when you split your fingers like you do (to throw it), you don’t really get a good feel for the ball,” Leyland said.

“Hopefully, we’ll get past that.”

Numbers say that Valverde will probably throw it more — but still not a ton.

And certainly not as much as he did once.

His first year in Detroit, Valverde threw the split-finger 52.5 percent of the time, and his four-seam fastball 47.5 percent, according to Fangraphs. In 2011, his usage of the split-finger dropped to 20.1 percent. Last season, it was down to 17.6 percent.

While he doesn’t throw the slider or change-up that he used in his early years, he’s added a sinker (two-seam fastball) to the repertoire the last two seasons.

That was one of the biggest concerns (or at least that’s the way it was interpreted), when the Tigers first thought about re-signing the veteran, despite saying early in the offseason they had no interest in a closer who’d essentially become a one-pitch pitcher.

There was some thought that it might have been a concerted effort by Valverde, who logged more than 200 combined innings over the last three seasons, to try and reduce the stress on his arm by not throwing the splitter as much. He says no.

“Depends on how you throw the split-finger,” he said of the stress the pitch can sometimes add to a pitcher’s arm. “A lot of people throw the split-finger, and it’s more like a forkball. My split is like a sinker.”

There’s also the factor of decreased velocity.

While his four-seam fastball sat around 95 mph during his two seasons with the Astros and his first here in Detroit, it dropped to an average of 93.9 in 2011, and 93.4 in 2012. It’s been at 92.6 so far this season.

Some of that, of course, is due to the lack of a true spring training.

Valverde joined the Tigers on April 23, after several outings in extended spring training and Class A.

The 35-year-old Valverde, though, said he feels fine, physically.

“I think everybody’s different,” he said. “I think I throw all my pitches, sometimes they’re not working like normal. And sometimes it’s working.”

While he’s still the team’s closer, Leyland wants to give Valverde every chance he can in non-save situations to work out some of the bugs that a veteran could normally smooth out in the spring. At the same time, the manager has been very reticent to push Valverde out there too frequently, and do something that might hurt him.

“We think we need to get him in better pitching shape. Not physical shape — he looks good, physically. He’s not too heavy or out of shape physically. ... Valverde’s in good shape, but not probably pitching shape. ... We felt like it’s important to get him out there and pitch him a little bit, get his arm strength up,” Leyland said.

“We think we gotta pitch him a little bit, but at the same time, you don’t want to hurt him. It’s kind of a balance.”

Monday’s appearance came just two days after Valverde blew his first save chance of the season.

“I want to be perfect, but I can’t be perfect,” the closer said, admitting that he set an unattainable standard with his 49-for-49 season in 2011 — but also noting that he did that without employing his split-finger as a primary weapon.

All the blown save did was again send warning bells off for those who haven’t forgotten his poor finish to the 2012 season.

Not necessarily for his manager, though.

“He looks good. He had a borderline pitch to (Cleveland’s Jason) Giambi the other day, 2-2. I’m tickled with him. He’s in good spirits. I think he’s in pretty good physical shape — probably not tip-top pitching shape yet,” Leyland said. “But I’m happy with him.”