A.J. Cole posted a 3.81 ERA with the Nationals in 2017. (Matt Slocum/Associated Press)

In the rankings posted after the 2011 season, Baseball America rated A.J. Cole as the 57th-best prospect in baseball. Xander Bogaerts ranked 58th on that list. George Springer ranked 59th. Sonny Gray and Chris Archer, starters in the 2017 All-Star Game, were among those ranked behind Cole that year, too.

Prospect rankings are notoriously fickle, but they illustrate the extent to which Cole was, at one time, one of the prized pitching pieces in a Nationals system then loaded with young pitchers. Now, as they are trying to reload their system with pitching prowess, Cole finds himself in an uncomfortable state of prospect purgatory. He enters the 2018 season out of options after three years spent shuttling between the minors and majors. He also enters the 2018 season as the man best positioned to seize the fifth spot in the Nationals’ rotation if the season started today, but he has not been convincing enough in his major league tenure to prevent the Nationals from pursuing someone to inherit that role before the season begins.

“I would love to be that fifth spot right now and progress on,” Cole said at Nationals Winterfest this month. “But if they need me in the [bullpen] or something like that, I will do that as well.”

Cole seems as likely to start the season in the bullpen as anywhere, as the Nationals seem committed to at least chasing a fifth starter, if not reaching for a middle-of-the-rotation type to provide depth behind their veterans. But as Nationals General Manager Mike Rizzo has talked about the need to add depth to his starting staff, he has also reiterated praise for Cole’s final six starts of 2017, a sample that encouraged some in the front office enough to feel comfortable with Cole as a sixth starter, or even regular rotation piece, entering 2018. In those last six starts, Cole averaged more than 5 1/3 innings per start and pitched to a 3.51 ERA.

“I feel like a lot of it was a lot of my strength. When I put on some weight, it really helped me,” said Cole, who spent much of his early prospect years working to add weight and struggling to keep it on through the course of a season. “Keep my stamina up, keep my strength up and help me progress through the season so I didn’t have to worry about, ‘Oh, my body’s tired.’ I was just able to go after it and do what I needed to do to get people out.”

That strength also helped Cole’s velocity return after two years of puzzling dips whenever he pitched in the majors. Whether because of the different ball, mound or stage, Cole’s mid-90s velocity didn’t translate through his first two seasons of spotty major league work. After his fastball averaged 91 mph in his first two season, his average velocity jumped to 93 in his major league work in 2017 — a substantial jump, by baseball standards. A mid-90s fastball was part of the arsenal that pushed Cole up those prospect rankings to begin with. A few years later, he was once again able to translate it.

Nothing about Cole’s arsenal wows these days. But he did attack more last season than he had in the past and threw fewer of the curveballs he used throughout the minor leagues and more of the slider he honed since his major league debut. In so doing, he was able to get weak contact, if not a standout ratio of swings and misses, and provide reliable quality starts down the stretch.

“In the past, I wasn’t throwing as hard in the big leagues. Just having that stamina there [helped],” Cole said. “And then being able to just go after the hitters with all my stuff. A lot of my stuff was working really well. I’ve been working on it, fine-tuning it, getting all my pitches to work and being able to throw it any time, any count.”

Cole will be 26 next season, which is a perfectly reasonable time for a pitcher to hit his major league stride. But the Nationals might not wait to see exactly what that stride looks like over the course of a major league season. They have had their eye on a starter since the beginning of the offseason, but if Cole can pitch to a 3.50 ERA (or even a more reasonable 3.80 or 4.00), he would constitute a cost-effective and perfectly tolerable fifth starter. But the Nationals rarely settle for “tolerable” when it comes to their rotation.

If they do acquire another starter, Cole seems likely to slide to the bullpen. Sending him to the minors would require surrendering him to waivers, where he would likely find some suitors. He has proved himself an effective long man and said moving from starting to the bullpen at times over the last two seasons has bothered him far less than pinging between the majors and minors.

Cole has pitched well enough to stay in the majors in one role or another, coming into his own as those antiquated prospect rankings anticipated he would — at least in part. But he enters his first season without options in a strange situation. He wants to be in the Nationals’ rotation for good and compiled a convincing showing down the stretch in 2017. But that showing might not have been good enough, leaving Cole floating in uncertainty just as he is finding his big league anchor.

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