The Pirates announced that left-hander Evan Sisk has been placed on the 15-day injured list (retroactive to July 1) due to inflammation in his throwing elbow.  Right-hander Hunter Stratton has been called up from Triple-A to take Sisk’s spot on the active roster.

Sisk has been one of the bright spots in Pittsburgh’s otherwise inconsistent relief corps, as the southpaw has a 2.23 ERA, 28.6% strikeout rate, and 8.6% walk rate over 36 1/3 innings and 32 appearances this season.  A hefty 86.6% strand rate has helped Sisk’s efforts and is probably the chief reason why his SIERA (3.13) and xFIP (3.65) are much higher than his real-world ERA.

That said, several of Sisk’s Statcast metrics are in the elite range, including some of the best hard-contact numbers of any pitcher in the league.  Sisk isn’t a hard thrower, but he has relied on his sinker, curve, and sweeper more often than his 91.1mph fastball this season, and this mix of pitches (which also includes a changeup) has kept both left-handed and right-handed hitting batters off-balance.

All of this good work has now been put on hold at least through the All-Star break.  It remains to be seen if Sisk can quickly get past his elbow soreness, or if the injury might be a precursor to something more serious.  Even if Sisk has avoided any kind of major elbow problem, a recovery timeline probably won’t be established until the left-hander is able to start throwing again.

Sisk was acquired from the Royals at last year’s trade deadline as part of the deal that sent Bailey Falter to Kansas City, and it is certainly possible that Sisk’s absence will impact Pittsburgh’s plans leading up to the August 3 deadline.  Even if Sisk is healthy, the Pirates will surely be looking to add to a bullpen that has been the team’s weak link.  The 44-45 Pirates are four games out of the wild card race despite a +21 run differential, and even average work from the pen would help get the Buccos more firmly into the postseason race.

Gregory Soto is the Pirates’ closer and fellow lefty Mason Montgomery‘s secondary numbers are much more impressive than his 4.54 ERA.  As such, the Bucs might not feel the need to specifically target another left-handed reliever if Sisk isn’t available, since the team realistically could use multiple relievers to shore up the bullpen.

Stratton’s call-up marks his official return to the Pirates, as the right-hander was optioned to Triple-A after being acquired from the Braves a couple of weeks ago.  Stratton made his MLB debut with Pittsburgh in 2023 and posted a 4.30 ERA over 52 1/3 innings in the back and gold before he was dealt to Atlanta last July.  This season, Stratton has spent most of the year in Triple-A and logged just one MLB game with the Braves.