By Matt Popchock

WASHINGTON (93-7 THE FAN/AP) — The Pirates gained ground on the idle Cardinals in the NL Central with a 6-5 win at Nationals Park Monday night, but they appear to have lost All-Star closer Jason Grilli indefinitely in the process.

Grilli entered in the ninth and gave up a two-run homer to Jayson Werth before leaving with an apparent arm injury after getting two outs.

Vin Mazzaro came on with Stephen Lombardozzi in the hole 0-1, and got him to ground out to second with the tying run on second for his first save of the year. Grilli was credited with his first hold of the season.

The Pirates later deemed the injury as “right forearm discomfort.” Grilli will be re-evaluated Tuesday.

The success of the 36-year-old righty, who had converted 30 of his first 31 save opportunities, had been one of the feel-good stories in Major League Baseball in 2013, prompting placement on a recent Sports Illustrated cover.

Prior to the injury, however, Grilli had begun to gravitate back toward career norms after a dominant first half of the season, having allowed eight runs in his past 10 2/3 innings. That includes the aforementioned homer by Werth, his second of the game, which made Grilli’s ERA swell to 2.34.

Historically, what the Pirates described ultimately points toward an elbow issue; Grilli did fracture his elbow in 2000, and underwent Tommy John surgery in 2002.

Having said that, the severity of this latest reported injury varies. Starting pitcher Wandy Rodriguez has been out since June 5 due to a combination of left forearm and elbow problems, and is projected to remain sidelined for another month. Long reliever Jeanmar Gomez had similar problems with his right forearm and was placed on the DL in early June, but returned within the month.

One very plausible candidate to fill the void left by Grilli would be setup man and fellow All-Star Mark Melancon. A closer for the Astros in 2011, Melancon has turned heads throughout this season as an eighth inning man for the 2013 Bucs with an 0.97 ERA, 0.82 WHIP, and 47 strikeouts against just six walks in 46 1/3 innings.

Stay tuned to SportsRadio 93.7 The Fan, your flagship home for Pirates baseball, for the latest.

(TM and © Copyright 2013 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2013 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)

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