Make or break time for Felix Doubront

Thursday night will see Felix Doubront make his first start of the season. At 26 years old, he's not quite in the "bright-eyed and bushy-tailed" camp anymore. In his two full years of service time, Doubront has been a part of one of baseball's most fractured teams, and one of its most cohesive. He's seen both the lows of a 90-loss team, and the heights of a World Series Championship.

And yet, even now, we don't necessarily have the best grasp on who Felix Doubront is on the mound. We know he's capable of quite a bit, as evidenced by his months-long run of strong starts in 2013. We also know that he can be erratic, has had trouble going deep into games, and perhaps most concerningly, has often faded as the year has drawn to a close.

Taken as a whole, the picture painted is one of a flawed but useful arm. A starting pitcher who can give you good outings, but can't be relied on when push comes to shove down the stretch. A reasonable #5, but probably not the kind a first-division team with Boston's resources wants to be penciling into the rotation for much longer.

Taken in parts, though...well, it depends on your interpretation. Is Felix Doubront a middle-of-the-rotation arm who, between inexperience and conditioning issues, has struggled to reach his full potential? Or is Felix Doubront a would-be middle-of-the-order arm but for a fatal lack of durability?

This year, with two full seasons behind him and a spring training that, finally, was free of conditioning concerns, it's all on the table with Doubront. If he is his usual self--which is to say good, but not superlative, and only temporarily--then the Red Sox will have reached the point where they can no longer offer him the benefit of the doubt in that department. And with so much young pitching on the way behind him with the potential to offer more, it might be time to find a new home for the lefty.

Ideally, though, 2014 will be different. Ideally, with a more successful spring training at his back, Doubront will be able to go the distance and establish himself as a quality MLB arm. While the Red Sox certainly have plenty of replacement options, with both Jake Peavy and Jon Lester's contracts coming to an end at the end of the season, having a team-controlled option that they can be more sure of than any of the prospects would certainly make assembling the next rotation a simpler task.

We won't know whether or not Doubront has managed to turn that page based on tonight alone. You can't test a season's worth of wear in one game. But there will be other things to look for. How much trouble does he have putting batters away? Will his improved conditioning allow him to stay fresh deeper into games? The fact that Doubront often had to throw quite a few more pitches to record the same number of innings in years past could certainly have had an impact on his ability to maintain effectiveness later in the season.

He'll have his chance to show us what he's got in the short-term tonight against the Orioles. But it's not the quick start we need to see out of Doubront. It's the impressive finish.