CHICAGO — Edward Cabrera, a starting pitcher who has long tantalized the Chicago Cubs with his potential, exited Wednesday night’s game against the Milwaukee Brewers with a right middle finger blister, the club announced.Cabrera walked off the Wrigley Field mound with an athletic trainer after throwing one pitch in the fourth inning. At that point, the Cubs trailed 4-0, with Cabrera’s outing marked by Pete Crow-Armstrong’s jarring second-inning error in center field, yet another sign of a team in a funk.Crow-Armstrong, the Gold Glove defender, missed what should have been a routine single up the middle for David Hamilton, Milwaukee’s No. 9 hitter. As the ball skipped past Crow-Armstrong toward the warning track, three runs scored during that sequence, giving Hamilton a Little League-style home run.

With the Cubs trying to avoid a three-game sweep against their division rivals, Cabrera covered only three innings, lasting 61 pitches.Previous injuries forced Colin Rea and Ben Brown into Chicago’s rotation, which no longer features budding ace Cade Horton, who’s recovering from season-ending surgery on his right elbow. Opening Day starter Matthew Boyd has progressed to the bullpen-session stage after a recent surgical procedure on his left knee. Justin Steele is scheduled for a follow-up visit next week with Dr. Keith Meister, who performed surgery on his left elbow last year and diagnosed him with a flexor strain last month.Cabrera’s extensive injury history with the Miami Marlins did not scare off the Cubs as they searched for rotation upgrades this past offseason. The Cubs gave up a trio of prospects — headlined by top prospect Owen Caissie — to acquire a pitcher who set a career high with 26 starts last year but possesses uniquely explosive swing-and-miss stuff.At 28, Cabrera has not yet reached 140 innings in a single major-league season. Nor has he lived up to expectations thus far with the Cubs (4.00 ERA through 10 starts), a point manager Craig Counsell acknowledged during Wednesday’s pregame media briefing.“I think he would expect better,” Counsell said. “And I think he has better in him.”