Dodgers pitcher Brandon McCarthy had Tommy John surgery Thursday morning at the Kerlan-Jobe Orthopedic Clinic in Los Angeles.

McCarthy faces a long rehab process, expected to last between 12 and 18 months, but he is not heading into uncharted territory.

Dodgers pitcher Brandon Beachy, whose locker stall sits to McCarthy’s left, has had two Tommy John surgeries. The man who will take his place in the rotation, Scott Baker, has had one.

“I’ve talked to (Baker), I’ve talked to Brett (Anderson), I’ve talked to Beachy,” McCarthy said Wednesday. “Unfortunately I’ve got a lot of friends — Jarrod Parker reached out to me, Daniel Hudson, same with (Chris) Capuano. That’s the thing with this. That many people have had it, I’m not Tommy John in this situation. I’m not going through it alone. Any questions that I have, there’s so much experience, I won’t hesitate to ask somebody.”

The answers McCarthy can expect to receive may vary.

Beachy needed only 13 months of recovery after his first Tommy John procedure before he pitched again in the major leagues, but he was 25 at the time of the surgery. Anderson was 23.

Baker was 30 when he had his procedure, just a year younger than McCarthy. Although he pitched 25 games last season for the Texas Rangers, Baker said he only recently gained the confidence to let loose on the mound.

“I did what I normally did pre-surgery” this past off-season, Baker said. “That’s allowing yourself to work hard and not have to do all this preventative stuff all the time. It’s not only physically tremendous, but mentally as well.”

But Baker also had a torn flexor tendon repaired when he had his ulnar collateral ligament replaced. Dodgers head athletic trainer Stan Conte, an expert in the field of Tommy John rehabilitation, said the tendon procedure is a tougher surgery to return from. Former Dodgers pitcher Chad Billingsley had the same procedure last June and is only now nearing a return with the Philadelphia Phillies.

To make an accurate projection of what the Dodgers can expect from McCarthy after he returns, one must dig a bit deeper into the data.

According to a master list of Tommy John recipients compiled by analyst Jon Roegele, McCarthy is the 92nd MLB player 31 years or older to undergo the procedure. John was the first. He was 31 when he had the surgery on Sept. 25, 1974.

Of the 92, nine were position players. That leaves 83 pitchers.

Nine of those pitchers were not in the major leagues at the time of their surgery. We’ll eliminate them to make a more accurate pre- and post-surgery performance comparison.

That leaves 74 pitchers in our group. However, 10 of them had already undergone the procedure when they were younger. They were not pitching with their God-given UCLs at the time of surgery. Another four pitchers had the procedure twice after they turned 31 (a fifth, Joe Nathan, just joined that group this week).

So we’re left with 60 major league pitchers including McCarthy who had their first Tommy John surgery at age 31 or older. Four haven’t had enough time to return to a major-league mound.

Among the remaining 56, there are some great success stories. The best seem to belong to relief pitchers. Fourteen pitched more than 100 games out of the bullpen after their surgery. One, John Smoltz, closed for four seasons, then became a starter again at age 38, then was elected to the Hall of Fame.

For starting pitchers like McCarthy, there are fewer models of stability. Only nine pitchers on our list (including Smoltz) started more than 100 games after their surgery.

The takeaway, then: For major league pitchers 31 and older attempting to return from their first Tommy John surgery, the majority (58.9 percent) did not pitch 100 games after their return. The odds of reaching that milestone are even lower for starters than relievers. Some never pitched in the big leagues again.

This is the reality facing McCarthy and the Dodgers, who signed the pitcher to a four-year, $48 million contract in December.

Conte put another disclaimer on the data: Many of the 31-and-over Tommy John patients were already on the downside of their careers. Maybe it wasn’t realistic to expect them to pitch another 100 games to begin with.

McCarthy said he isn’t Tommy John. Yet arguably the most successful, comparable case study might be John himself. He was 31 and in his prime with the Dodgers when team physician Dr. Frank Jobe performed the first-ever ligament replacement surgery.

John pitched 355 games before his surgery and another 405 after, almost entirely as a starting pitcher.

McCarthy has appeared in 211 games in his career, 157 as a starter. Maybe he ought to hope that he is Tommy John after all.