PITTSBURGH — The Pittsburgh Pirates saw one of their better players leave their most recent contest.Pirates first baseman Spencer Horwitz didn't come out for his scheduled at-bat in the bottom of the fourth inning, as Esmerlyn Valdez came into pinch-hit for him. Valdez would eventually move to right field, as Tyler Callihan took over in place of Horwitz in the top of the fifth inningThe Pirates announced that first baseman Spencer Horwitz left the game due to left hamstring discomfort and that the Pirates medical staff is currently treating him and examining him.The Pirates have gotten great production from Horwitz this season, who has become a massively important part of their lineup.Horwitz has slashed .280/.386/.455 for an OPS of .841 in 74 games, with 69 hits, 11 doubles, 10 home runs, 33 RBI and 40 walks to 40 strikeouts.He ranks sixth in the National League and 12th in MLB with a .386 on-base percentage, while his 40 walks rank tied-13th in the National League and tied-27th in MLB.The Pirates will hope that Horwitz doesn't miss much time and that this isn't a long-term injury for him. Make sure to visit Pirates OnSI for the latest news, updates, interviews and insight on the Pittsburgh Pirates!Add us as a preferred source on GoogleFollow