Felix DoubrontBOSTON — Who is the real Felix Doubront?

We’re not much closer to answering that question than we were six months ago. Doubront has been on somewhat of a rollercoaster this season, and there’s a good chance that we’ll enter next spring training wondering what exactly the left-hander will provide in 2014.

Doubront made what is expected to be his final start of the 2013 season on Sunday. He went seven innings against the Blue Jays while earning his 11th win of the year. The left-hander gave up two runs on four hits while striking out two, walking two and throwing 97 pitches (61 strikes). It was a solid effort after a lengthy layoff and back-to-back starts in which he failed to make it out of the fourth inning.

“He was very good. Much more powerful than the last few times out,” manager John Farrell said. “The additional rest we were able to provide him seemed to pay off. A lot of strikes. Maybe not the number of strikeouts we’re used to seeing from Felix, but I thought he carried his stuff through the full seven innings. He was efficient. They were aggressive early in the count. He went to his changeup when he needed to. Overall, he repeated his delivery. He just looked more fresh and rested and that was the case. A solid seven innings of work.”

Doubront will now shift to a relief role, although it’s unclear whether the Red Sox will carry him on their postseason roster. The left-hander pitched out of the bullpen in 2011, but all but one of his appearances since then has come in a starting role. Doubront could end up being a roster casualty given the Red Sox’ already lefty-laden bullpen.

If we have indeed seen the last of Doubront in 2013 — at least as a starter — it marks the end of a wild season for the southpaw. Doubront was very shaky in the early going, as his ERA ballooned to 6.40 by May 8, but the lefty eventually settled down and became a consistent force at the back end of Boston’s rotation. Doubront gave up three earned runs or fewer in 15 straight starts from May 16 to Aug. 10.

“There was that 15-start stretch where he was as consistent as anyone in our rotation,” Farrell said. “He’s a talented left-hander. He’s got a full complement of pitches. He’s got some swing-and-miss to his fastball. We’ve talked about a number of times this year where different guys have stepped up and in that stretch, he was as good as anybody who was also in the rotation at the time.

“I make reference to the talent because you see a guy who threw 160 innings I think on the regular season, 11-6. You view Felix as a guy that there’s more in there and he’s capable of more. It comes down to more the physical side of it and the endurance throughout the whole season.”

Doubront’s conditioning has been a concern the last two seasons, and it’s what could ultimately keep him from reaching the next level. While Doubront enjoyed a ton of success in the middle of the season, he appeared to break down recently, forcing the Red Sox to give him some extra rest. Doubront responded well to the break in action, but until he proves he can go close to 200 innings, his overall value isn’t as high as it could be.

“He’s always been a guy with very good aptitude,” Farrell said. “When he first came up, pitched out of the bullpen, he’s got a willingness to learn. And yet not being here ago, just talking with those who have seen him throughout the course of his first full season [in 2012], I know he had to get shut down for a couple of weeks last year just to regroup. But to me, the only thing that limits him currently is just the stamina and the endurance over the course of a full season. Like I said, he’s an extremely talented young guy.”

It’s easy to forget that Doubront is still just 25 years old. There’s certainly time for him to work on improving his stamina, and he’ll once again be an intriguing storyline next season. If there is one thing we learned about Doubront this year, it’s that there’s a very consistent pitcher in there somewhere. It’s simply a matter of making sure that pitcher is in good physical shape for a full 162-game slate.

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