At age 22, Shelby Miller produced a season for the St. Louis Cardinals which was good enough to finish third in National League Rookie of the Year voting. In 173 1⁄ 3 innings, Miller posted a 15-9 win-loss record with a 3.06 earned-run average. He was a bit less illustrious by fielding-independent pitching, but he still trailed only Adam Wainwright and Lance Lynn by FanGraphs Wins Above Replacement. Shelby Miller produced, by his lesser WAR measure, the best season by a Cardinals pitcher who was 22 or younger since Rick Ankiel in 2000 (I always worry when I reference Ankiel’s pitching career that younger readers have a “Ronald Reagan, the actor?” moment).

Shelby Miller took a step back in 2014; his ERA was fine, though worse than 2013 at 3.74, but it was his 4.54 FIP which caused more worries among Cardinals fans and the Cardinals organization—he was no longer the strikeout-oriented pitcher of his rookie campaign, averaging just 6.25 strikeouts per nine innings, while his bases on balls rate increased by nearly half a walk per game.

The Cardinals had a surplus of young pitchers capable of serving in the starting rotation, and because of the death of top outfield prospect Oscar Taveras, a desperate need to find an everyday starting right fielder, as the organization was not yet ready to depend on Randal Grichuk as an everyday corner outfielder. The Atlanta Braves were in the nascent stages of what they hoped would develop into a Houston Astros or Chicago Cubs style top-to-bottom organizational rebuild.

The two organization’s needs aligned, so the Cardinals traded Shelby Miller, a year removed from being a Rookie of the Year finalist and two years removed from being the organization’s best prospect, and pitching prospect Tyrell Jenkins, to the Braves for right fielder Jason Heyward and reliever Jordan Walden.

Jenkins and Walden were considered somewhat of afterthoughts at the time of the trade, and their performances with their new clubs reflected this—Jenkins struggled mightily for the Braves in 2016 and is now producing similarly poor numbers for the El Paso Chihuahuas, the AAA affiliate of the San Diego Padres; Walden was successful in his scant time with the Cardinals but is presently out of baseball following issues with his pitching arm. When it comes down to it, this is the Shelby Miller and Jason Heyward trade.

From the Braves’ perspective, they “won” the trade, though this was almost certainly going to be the case from the beginning. They finished 67-95 in 2015 with Shelby Miller but were not going to finish near a playoff position with Heyward (the same is probably also true if they’d added Mike Trout and Clayton Kershaw), and re-signing Heyward, who became a free agent after the 2015 season, was not going to align with the rebuilding process.

But how does this trade, with nearly two-and-a-half years of hindsight, look for the Cardinals?

Shelby Miller had a very promising 2013 rookie campaign and struggled in 2014, but in 2015, after being traded to the Braves, Miller had his best season in the Majors. His win-loss record was poor—he went 6-17—but his 3.02 ERA was the 14th best in baseball. Once again, his peripherals were worse than his run suppression, but with 3.4 fWAR in 205 1/3 innings, he was proving himself to be no worse than a solid MLB starter.

As a Cardinal, Jason Heyward was worth 6.0 fWAR, 2.6 more than Shelby Miller that season. But in the specific case of the Cardinals, Heyward was more valuable than this—Grichuk turned out to be solidly above replacement level in 2015, and he would have been fine in right field, but this also would mean Grichuk could not play in center field, meaning more playing time for Jon Jay (a 57 wRC+ in 245 plate appearances and only above replacement level thanks to defensive metrics well out of line with his career norms) or Peter Bourjos (a 69 wRC+ in 225 PA with career-worst defensive stats, but even assuming these metrics were a fluke, he was unlikely to be a great option). Perhaps Stephen Piscotty could have played as well in the first half of 2015 at the MLB level as he did in the second half, but even so, his 2015 fWAR prorated to Heyward’s total number of plate appearances, 610, was 2.6—good, but not Heyward.

Meanwhile, Miller’s absence from the Cardinals rotation opened the door for Carlos Martinez. In 2015, Martinez was a shockingly similar pitcher to Miller—a 3.01 ERA, 3.21 FIP, and like Miller, 3.4 fWAR. Martinez was unable to pitch in the postseason, so in that regard, having Miller might’ve been nice (assuming Miller would’ve pitched in the postseason), but without Jason Heyward, the Cardinals might not have made the NLDS in the first place—despite 100 wins, the 98-win Pittsburgh Pirates and 97-win Chicago Cubs meant that the Cardinals had to fight tooth and nail for the division crown. Even going strictly by fWAR, never mind the value of the actual replacements, Heyward was the difference between the NLDS and needing a Wild Card game to make it.

In 2015, the trade worked. This was always necessary for the trade to, on balance, be a good one for the Cardinals—whether Heyward re-signed with the Cardinals was irrelevant in evaluating the trade, because he could have signed with the Cardinals after the 2015 season regardless of where he had spent the previous season.

In 2016, Jason Heyward took a fairly significant step back—his right field defense remained elite, but he was a slightly below-average overall player due to his disastrous offense—his 72 wRC+ was not only by far the worst of his career, but the fourth-worst qualified offensive season in baseball. But this doesn’t matter—Heyward’s 2016 wasn’t part of the trade. Shelby Miller’s 2016 was, and as disappointing as Heyward was last season, Miller was far worse—his peripherals got worse, with his FIP and xFIP jumping to new career highs of 4.87 and 5.06, but for the first time in his career, his ERA was worse than these fielding-independent statistics—his ERA jumped to 6.15.

But this did not hurt the Atlanta Braves. While the Cardinals had arguably sold low on Miller after 2014, the Braves sent Miller (and Gabe Speier) to the Arizona Diamondbacks for Ender Inciarte (this was the point in hearing about the trade that I thought the Braves probably won the trade), top-100 prospect Aaron Blair (well, um, okay, I don’t agree but I guess I see what Arizona is doing), and 2015 #1 overall pick Dansby Swanson (WAIT, WHAT, NO, TONY LARUSSA, DAVE STEWART, WHAT ARE YOU DOING?!?!).

If the alternative to trading for Jason Heyward was keeping Shelby Miller into infinity, it is increasingly looking like the trade was a good idea. Miller certainly would have hurt the Cardinals’ chances last year—by the time the team figured out that he was no longer qualified to be in their rotation, they would have lost extra games as a result. Miller bounced back somewhat, though to no better than average, to start 2017, but he is now out of commission following Tommy John surgery.

But what if the Cardinals held onto Miller through 2015 and had the foresight to know that Miller would falter (and also that Carlos Martinez was more than capable of pitching in a Major League rotation), thus acquiring Swanson, Inciarte, and Blair? It was a one-in-a-million trade—it has been retrospectively maligned, but consensus was overwhelmingly that it was a steal for the Braves from the beginning—but if the Diamondbacks were willing to give that package to the Braves, they would surely also be willing to give it to the Cardinals.

In 2016, Ender Inciarte was worth 3.6 fWAR, primarily in center field. He was a stone’s throw from league-average offensively (his wRC+ was 97) but had very strong defense and above-average base running. Had all three of the players acquired for Miller been in the Cardinals organization, he is likely the only one who would have logged significant playing time in MLB in 2016—Dansby Swanson was just 22 and in his first full professional season, and despite the lack of confidence in the shortstop position prior to Aledmys Diaz’s breakthrough, if the Braves weren’t willing to give him a chance until August 17, the Cardinals probably wouldn’t have early either (and even if they would later, Diaz’s emergence would make such a move less likely). And Aaron Blair, terrible in big-league duty, would have been best served spending the entire season in Memphis.

2016 brought us Kolten Wong and Stephen Piscotty logging time in center field. The Cardinals missed a Wild Card spot by one game. Ender Inciarte probably would have made the difference.

But the Chicago Cubs would have still easily won the NL Central. In reality, the Cardinals made the NLDS once and missed the playoffs once. In keeping Miller for 2015 and then trading Miller to the Diamondbacks, the Cardinals would likely win zero NL Central titles but make the Wild Card game twice, probably hosting it in 2016 and playing the 2015 edition in Wrigley Field but being in veritable coin-flip games. This is probably close to a push, though I’d give a slight edge to reality. The expected NLDS appearances following these Wild Card games is probably slightly less than one, as their opponents would have had slight pitching advantages—in 2015, facing Cy Young winner Jake Arrieta, and in 2016, facing Johnny Cueto (since the San Francisco Giants would have used Madison Bumgarner in a Wild Card play-in game against the Mets, essentially duplicating the Wild Card game from last season which the Giants won).

Of course, going forward, the trade should be paying more dividends. But it’s hard to know for sure. Aaron Blair has been promoted to the Braves, but was walking 5 1⁄ 2 batters per nine innings in AAA Gwinnett. Dansby Swanson has been sub-replacement level in 2017, and while I’m certainly not giving up on the guy, it should be noted that he was considered a lesser #1 overall pick than can’t-misses like Bryce Harper or Stephen Strasburg. I’d certainly take him, but he’s not as sure-fire as Braves fans might want to believe. And Ender Inciarte too has been far less dynamic in 2017.

If the choice is between 2015 Jason Heyward and 2015-onward Shelby Miller, the Cardinals almost certainly made the right decision. If the choice is between 2015 Jason Heyward and 2015 Shelby Miller, plus the return that Miller commanded in a trade, it’s a bit more complicated. Knowing what the Miller return has produced so far, it’s essentially a push, with perhaps a slight edge to Heyward, though going forward, it’s hard to not prefer the upside of Swanson and present-day MLB usefulness of Inciarte. With that said, the Braves certainly had no illusions themselves of turning Heyward into these multiple players—they just happened to be in the right place at the right time, with the right trade chip being dealt to the right organization.