At least the Diamondbacks have found a way to win when he faces the San Diego Padres.
Winless in eight weeks, McCarthy gets the ball in Friday night's series opener in San Diego against a Padres team coming off the wrong end of a no-hitter.
After finishing second in the NL West last season, the Diamondbacks (33-48) have been bringing up the rear of the division ever since a 5-18 start. Arizona's woes stem from a starting rotation that owns a 4.81 ERA - one of the worst in the majors - and McCarthy (1-10, 5.38 ERA) has been one of the staff's biggest weaknesses.
Arizona, which has dropped 10 of 14 after Wednesday's 6-1 loss to Cleveland, has grown quite accustomed to losing when McCarthy takes the hill. The Diamondbacks have lost 14 of his 16 starts, but those victories have come in the right-hander's only two outings against the Padres.
His lone win came at San Diego on May 3, when he tossed three-hit ball over seven scoreless innings in a 4-3 final. He wasn't nearly as sharp in the rematch May 26, permitting five runs and nine hits in 6 2-3 innings, but the Diamondbacks rallied for a 7-5 victory.
That outing began a six-start stretch for McCarthy in which he owns a 6.62 ERA. He yielded five runs and 10 hits in five innings of Sunday's 6-4 loss to San Francisco to become baseball's first 10-game loser.
"The frustrating thing is I don't have any more answers this week than I did last week or the week before," he told MLB's official website. "I don't know what the heck I'm doing wrong. ... It just doesn't seem to be coming together."
Nothing came together Wednesday for the Padres, who were no-hit for the second time in less than a year by Tim Lincecum in a 4-0 loss to the Giants.
San Diego (34-45) is last in the majors in runs per game (3.0), batting average (.213) and OPS (.610) but showed signs of life offensively in winning the first two in the series with San Francisco, combining for 13 runs and 20 hits. It then managed only a Chase Headley walk against Lincecum.
No. 3 hitter Seth Smith, who was 4 for 8 with a double in the first two games at San Francisco, is 3 for 6 with three doubles against McCarthy this season.
San Diego counters with Tyson Ross (6-7, 3.22), who has alternated good and poor outings in four starts this month. He has an 8.18 ERA in two of those games and a 1.29 ERA in the other two. He's winless in all four, however, as he hasn't been backed by a single run of support.
''I don't worry about that because I have no control over it,'' the right-hander said after allowing three runs in seven innings of Saturday's 4-2 loss to the Dodgers. ''I just try to concentrate on my end and give us a chance to win.''
Ross opposed McCarthy on May 26 and gave up five runs in five-plus innings. He had a 1.86 ERA in his first four starts versus Arizona.
Paul Goldschmidt is 5 for 14 with two homers lifetime against Ross, but he's 1 for 14 with seven strikeouts and seven walks in his last four games. He is batting .409 with two home runs in six games against the Padres this season, with the Diamondbacks winning four.