Was This the Worst-Pitched Season in Marlins History?

The on-field history of the Florida/Miami Marlins has been filled with glorious highs and agonizing lows. The franchise rightfully owns two World Series championships (1997 and 2003). But of the 29 seasons they’ve played, a mere 7 of them have resulted in a winning record. These mostly mediocre ballclubs have featured many inconsistent performers.

A resolution to the lockout is hopefully in the not-too-distant future. In the meantime, we continue to reflect on the team’s history.

Today’s subject: Adam Conley and his disastrous 2017 season, and that is putting it politely. It might very well be the worst single season authored by any Marlins pitcher.

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First, a bit of backstory on the lanky-left-hander.

Debuting with the club during the 2015 season, Conley initially proved commendable. He authored a respectable 3.82 ERA (102 ERA+) and 4.02 FIP through 200.1 IP across 40 appearances (36 starts) between 2015-16. Even then, concerns existed to the tune of a 1.36 WHIP and a BB/9 of 4.2 in his sophomore effort in 2016.

Conley was slotted into a back-end starting rotation spot entering 2017, poised to prove himself over the course of a full-length season. This would be where everything seemed to fall apart.

A 5-inning, 1-run, 1-hit performance in his first start on April 8 provided fans false hope for what was about to ensue. Later that month, Conley would allow 9 earned runs—recording just five outs—in a 12-2 loss to Pittsburgh. Then two weeks later, Conley would be tagged for 7 runs over 3 ²⁄₃ innings against St. Louis. The Marlins responded by demoting him to AAA, not to return to the big league level until after the All-Star break.

Up to that point, Conley had a 7.53 ERA over 28 ²⁄₃ innings, with hitters slashing .257/.356/.469 against him.

Following his recall in mid-July, the former second-round draft pick again teased us with a glimpse of good production. Conley allowed just 4 runs over 20 ²⁄₃ innings that month (1.74 ERA); as for his last 11 appearances, he struggled to the tune of a 7.09 ERA. This time, hitters would post a collective .922 OPS against the left-hander.

Overall, Conley finished the year with an 8-8 record, though his real performance should be judged by the 6.14 ERA and not much better 5.62 FIP over 102 ²⁄₃ innings.

Of the 134 MLB pitchers to pitch at least 100 innings in 2017, Conley would place 130th in ERA. Each trailing pitcher threw their innings in the American League, a league where the presence of the DH generally assumes the idea of it being a harder league to pitch in. Conley posted an adjusted ERA+ of 65, meaning he was 35-percent worse than the average pitcher when contextualizing the pitcher’s run-scoring environment. That was the second-worst mark of any above-qualified pitcher, with Baltimore’s Ubaldo Jiménez trailing the pack at 64.

Stathead | Baseball-Reference

In Marlins franchise history, there has never been anybody else like 2017 Adam Conley.

Conley’s aforementioned 65 ERA+ is worse than any other Marlin with at least 100 innings pitched. By Baseball-Reference’s version of WAR, he was worth -1.4 wins in 2017—even if we lower the innings threshold to 50, he’d still reside in the bottom 10 among all pitchers.

Remember Andy Larkin? Most fans would like to forget his name considering what he did in 1998. Pitching to an eye-popping 9.64 ERA (42 ERA+) in his first extended run against big league hitters, Larkin finished the season with -3.2 rWAR, the lowest accrued by any Marlins pitcher over the course of a single calendar year. However, he was mercifully limited to 14 starts and 74 ²⁄₃ innings. Larkin performed below Conley’s standards, but didn’t provide nearly as much volume of undesirable production.

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Why did Conley suddenly lose so much of his effectiveness?

While not the hardest thrower at the outset of his career, Conley’s fastball velocity made him an especially easy target in 2017. Previously in the 33rd and 38th percentile among major leaguers, he finished in the 14th percentile in 2017. He induced just 6.3 K/9 (another career-low).

Baseball Savant

Bob Seger once sang about turning the page, but the new Marlins front office installed during the 2017-18 offseason didn’t have that on their playlist. Conley was denied of the opportunity to re-establish himself as a starter. While a relief role did enhance his fastball velo, he continued to be a sub-replacement-level pitcher.

The Marlins’ brass severed ties with Conley in 2020. Last season, he scrapped his plans to pitch in Japan and landed a modest minor league deal with the Tampa Bay Rays. After several months of biding his time at AAA, he flaunted his true talent at the highest level, pitching to a career-best 2.29 ERA (4.09 FIP) and 1.01 WHIP (albeit in just 19 ²⁄₃ innings).

Countless professional pitchers would be envious of what Conley has achieved. Perhaps his signature season is still to come (after all, he’s only 31 years old). For now, unfortunately, the most distinctive aspect of his career is the way he combined poor performance and high usage for the Marlins in 2017.