Why isn't Shawn Kelley in the mix to be the Nationals' closer?

Any and all talk of the as-yet-undetermined identity of the Nationals' 2017 closer has boiled down to two conclusions: Either the Nats need to acquire an experienced reliever who has a track record of success pitching the ninth inning, or they should give one of their young, in-house relievers (most notably Koda Glover) the opportunity to seize the job.

Along the way, though, we seem to have glossed over one other potential resolution to this problem. It's another in-house candidate, but one who has experience, just not much of it in the ninth inning: Shawn Kelley.

One of the best setup men in the league this season, Kelley seemingly has been typecast for that role, with few suggesting he could just shift from the eighth to the ninth inning, where he might turn out to be quite effective.

Don't think Kelley has closer stuff? Take a closer look at that ...

* The 32-year-old had an 0.897 WHIP this season. That ranked seventh-best among all major league relievers who pitched at least 50 innings. He was better than Mark Melancon, and only percentage points worse than Aroldis Chapman.

* Kelley struck out 12.41 batters per nine innings, which was 10th-best among all big league relievers with at least 50 innings.

* Kelley's 7.27 strikeout-to-walk ratio was third-best among that same group of relievers. The only guys in baseball better than him? Andrew Miller and Kenley Jansen.

It almost seems too obvious a choice. So why hasn't it been discussed more? Is there a catch?

Well, yes. Actually, there are a few.

We'll start with the state of Kelley's arm, which has a lot of mileage on it, not to mention two Tommy John surgeries. When last we saw him, he was walking off the mound during Game 5 of the National League Division Series with an apparent injury that he later revealed included numbness in his fingers. (Kelley insisted that night he was fine, and the Nationals have since concurred.)

Trouble is, the team took significant steps this season to avoid overworking Kelley. He pitched on back-to-back days only 16 times. And it wouldn't be wise to ask much more than that of him in 2017, given his health history.

Kelley also isn't exactly a world-beater against left-handed batters. He was brilliant against righties this season, holding them to a .176 batting average, .203 on-base percentage and .539 OPS. He was still pretty strong against lefties, who hit only .225 with a .279 on-base percentage against him. But those batters did rack up a .792 OPS against him, a product of 11 extra-base hits in only 80 at-bats.

Kelley does have a penchant to give up the longball, surrendering nine of them in 58 innings. That's not a trait you typically want from a closer.

So Kelley does not necessarily check all of the boxes when determining whether a reliever is ninth-inning material.

Still, the Nationals could do a whole lot worse than an experienced right-hander who doesn't give up many hits or walks, strikes out batters at a high clip and doesn't get fazed by pressure situations.

The club's preference probably remains to acquire a more proven closer who has pitched elsewhere in the past. But if that doesn't happen, Kelley should at least be in the conversation when team officials debate their in-house options for the ninth inning.