Upstart Miami Marlins recall top pitching prospect Andrew Heaney

Andrew Heaney's promotion is just a number of recent moves the Marlins made to their roster. (Carlos Osorio/AP) Ace Jose Fernandez is out for the rest of the

Andrew Heaney's promotion is just a number of recent moves the Marlins made to their roster. (Carlos Osorio/AP)

Ace Jose Fernandez is out for the rest of the year due to Tommy John surgery, but the upstart Marlins have another pitching phenom on the way. The team recalled 23-year-old Andrew Heaney, considered the game's top left-handed pitching prospect, from its Triple-A New Orleans affiliate. He'll debut Thursday at Marlins Park with a start against the Mets.

The ninth pick of the 2012 draft out of Oklahoma State, Heaney climbed the ladder in the Marlins organization so quickly he has never accumulated more than 61 2/3 innings at any stop. Sidelined until May 26 of last year due to a lat strain, he split his season between High-A Jupiter and Double-A Jacksonville, compiling a 1.60 ERA with 8.4 strikeouts per nine in 95 1/3 innings. That performance earned him the number 30 ranking on the top prospect lists of both Baseball America and Baseball Prospectus. He's the highest ranked southpaw on either list. He made nine appearances at Jacksonville this season before being promoted to New Orleans. In 76 2/3 innings across two levels, he's put up a 2.47 ERA with 9.3 strikeouts per nine and a stellar 5.3 strikeout-to-walk ratio.

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The 6-foot-2, 185-pound Heaney offers a pair of plus pitches with his fastball and slider. Via a deceptive delivery featuring an arm slot slightly below three-quarters, he works 89-93 mph with his four-seamer but can ramp it up to 96 when he needs it. His slider shows good tilt and angle, and he can throw it either in the zone or as a chase pitch. His changeup has the potential to be an above-average pitch as well. His ceiling is as a number two starter, with a number three profile perhaps more realistic.

Even without Fernandez, who last pitched May 9 before undergoing surgery, the Marlins have surprised the baseball world this season. On the heals of an expensive 93-loss debacle in 2012 and an embarrassing 100 losses last year following their fire sale, they're 35-33 thus far, tied for second with the Nationals in the NL East, just a game behind the Braves. As a unit, their rotation's 3.98 ERA ranks just 10th in the league, their 51 percent quality-start rate ninth, but that's largely due to their struggles at the back of the rotation. Their only pitcher to make more than four starts with an ERA above 3.71 is Jacob Turner, who has been sent to the bullpen with his 6.38 ERA. Henderson Alvarez (2.56 ERA, 151 ERA+) has tossed three complete-game shutouts, while Tom Koehler (3.68 ERA, 105 ERA+) and Nathan Eovaldi (3.71 ERA, 104 ERA+) have both been better than average, though the former has far outdone his peripherals, including a beefy 4.0 walks per nine.

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Heaney will join that trio, as will 24-year-old righty Anthony DeSclafani, who was recalled as part of  a flurry of roster moves Monday. DeSclafini made two starts for the team last month and has put up a 3.92 ERA with 8.3 strikeouts per nine at Double-A and Triple-A. As for the other moves, 37-year-old lefty Randy Wolf (5.26 ERA in 25 2/3 innings) was designated for assignment after just four starts, as was 30-year-old righty swingman Kevin Slowey. Additionally, left fielder Christian Yelich was placed on the 15-day disabled list due to a lower back strain, while catcher Jarrod Saltalamacchia transferred from the seven-day concussion disabled list to the 15-day DL.

They scratched Heaney