There’s no questioning that the Colorado Rockies’ rotation has been awful this season. In fact, by way of FIP-, the 2015 Rockies have the third worst rotation since 1915. As of this writing, not a single Rockies pitcher with more than 10 starts has a FIP that’s even above-average this year — which leaves fans with little to look forward to. That’s about to change, though, as the Rockies have summoned 23-year-old top prospect Jon Gray from Triple-A Albuquerque to start tonight’s game against the Mariners.

The Rockies drafted Gray third overall in the 2013 amateur draft out of the University of Oklahoma, and he immediately began to perform in the minor leagues. He closed out his draft year by pitching to a 1.93 ERA and 1.88 FIP in nine starts between Rookie Ball and High-A. Gray appeared to be on the fast track to the majors after such an exciting debut, but his performance tailed off substantially in Double-A last year. After striking out 26% and 42% of batters faced in Rookie Ball and High-A, respectively, he whiffed just 22% at the Double-A level. Along with a 8% walk rate, this resulted in a middling 3.91 ERA. KATOH forecasted Gray for just 2.3 WAR through his age-28 season.

The Rockies moved Gray up to Triple-A this year, and on the whole, his numbers look very similar to the ones he put up in Double-A. Once again, his strikeout rate (22%) and his walk rate (8%) are very close to league average. And once again, he pitched to an unremarkable 4.33 ERA. His 3.89 FIP wasn’t much better. Still, while the performance was largely the same, Gray’s KATOH forecast to jumped up to 4.2 WAR through age-28 year due to his pitching at a higher level. His improved projection would have put him 88th overall on KATOH’s preseason list.

That’s certainly better, but it still feels like a very pessimistic forecast for Gray, who was a consensus top-30 prospect for two years now. A closer look at Gray’s trajectory suggests his full-season 2015 numbers might not be doing him justice. Gray got off to a rough start to 2015, but he has pitched markedly better lately. Over his past six starts, he’s pitched to a 2.15 FIP and struck out 33% the batters he’s faced. His strikeouts have been trending up since mid-June or so.

Meanwhile, his FIP has been on the decline.

In terms of stuff, Gray has everything you look for in a starting pitcher. His fastball sits in the 91 mph to 94 mph range, according to Kiley McDaniel. And more importantly, his slider and changeup both project to be above-average pitches in the near future, which makes for a solid three-pitch mix.

On the downside, Kiley’s noted that Gray’s stuff has ticked down a couple of notches in the two years since he was drafted. Gray would touch 100 mph in his later days on Oklahoma’s campus, but he rarely tops 95 mph now. Some of this decline may have been intentional, as the Rockies have been working to smooth out the right-hander’s delivery. Nonetheless, this very well might help explain why Gray started missing fewer bats after his first season as a professional.

Let’s pull up some comps. Using league-adjusted, regressed stats, along with age, I calculated the Mahalanobis distance between Gray’s 2015 stats and every season at Triple-A since 1991 in which a pitcher faced at least 350 batters. Below, you’ll find a list of historical players whose performances were nearest and dearest to Gray’s, ranked from most similar to least similar.

*Pitchers who have yet to play their age-28 seasons.

There are some pretty impressive names in this group. Homer Bailey, Jason Hammel, Sonny Gray and Jason Jennings all turned into solid major leaguers. Even Rodrigo Lopez, who’s Gray’s top comp, was better than you probably realized in the early oughts. However, several of the pitchers listed above weren’t nearly the same caliber of prospect as Gray. Alfredo Figaro? Dave Haas? Who are you?

To weed out all of these non-prospects, let’s thin the field a bit. Here’s a look at the guys who were either drafted in the first round or cracked Baseball America’s top 100 list the winter before their Gray-esqe seasons.

*Pitchers who have yet to play their age-28 seasons.

That looks a little more appropriate. It’s reasonable to expect Gray’s career trajectory to resemble some of these pitchers. In other words, there’s a good chance he falls somewhere between Jeff Niemann and Homer Bailey, which wouldn’t be a bad outcome by any means.

Everything about Gray suggests he’s an awfully good bet to be a solid big-league starter. This is especially true if you buy into what he’s done these past couple of weeks. Whether he’s ready to be that guy right away, though, is up for debate. Steamer, with its 4.32 ERA rest-of-season forecast, suggests he’s not quite there yet. But it seems foolish to bet against a guy with Gray’s stuff who’s been nearly unhittable for the past month or so. Seeing how the Rockies are well out of the race, Gray will almost certainly finish out the year in their rotation, regardless of how he performs. At the least, the 23-year-old’s starts should be fun to watch.