The rookie looks to bounce back from perhaps his worst performance in the majors in what could be his final shot in the rotation Tuesday night, when St. Louis opens a three-game series with the visiting Arizona Diamondbacks.Kelly (2-5, 3.47 ERA) got the call from Triple-A Memphis when Garcia went down with a left shoulder sprain in early June, and included in his first 11 major league appearances is a stretch of seven straight quality starts.That run ended when he allowed three runs and 12 baserunners over 5 2/3 innings Aug. 3 against Milwaukee, and he was even less effective Wednesday. The right-hander was charged with seven runs -- four earned -- and nine hits over five innings in a 15-0 loss to San Francisco.Not exactly the best time for a rough outing considering Garcia could make his first start in the majors since June 5 on Sunday."When I'm scheduled to pitch, I pitch," Kelly told the team's official website when asked about such speculation. "I don't look into that at all, really."The Cardinals (62-53) open a nine-game homestand Tuesday and are in the midst of a stretch of 16 of 19 at Busch Stadium, while the Diamondbacks just finished their lone home series in a span of 19 games. Arizona salvaged the finale against major league-best Washington 7-4 on Sunday as five of its six hits went for two bases.The Diamondbacks (58-57) are within striking distance of both the top spot in the NL West and wild-card leaders Atlanta and Pittsburgh, but manager Kirk Gibson isn't pleased with a team that's made 10 errors in its last seven games."We have to play a cleaner game," Gibson said Sunday prior to Arizona's 30th game in 31 days. "There is a bit of fatigue, so there are going to be mistakes. We're trying not to, and we moved on very quickly. It's very frustrating for everybody, but we move on and get back after it. We've lost some tough games."Ian Kennedy's latest start was perhaps his toughest -- and unquestionably his shortest -- of the season. Arizona gave the right-hander a 2-0 cushion in the first, but Kennedy (10-9, 4.34) immediately surrendered the lead and wound up allowing six runs over four innings in a 7-6 defeat."I just didn't execute at all tonight," Kennedy told the team's official website. "It's frustrating. We're trying to go for this NL West race, and to pitch like that was not acceptable. I can't say how frustrating this is."That's likely how he felt May 8 versus St. Louis, when he gave up six runs in the first two innings before settling down to go seven in a 6-1 loss. That dropped Kennedy to 1-2 with a 10.13 ERA in three career starts against the Cardinals.St. Louis swept that three-game set in the desert and has outscored Arizona 33-17 while winning five straight in the series.Three of the Cardinals' eight homers against the Diamondbacks in May came from Carlos Beltran, who seems to torment Arizona regardless of where he's playing. The NL RBI leader with 83, Beltran is hitting .431 with a 1.338 OPS in 15 games against the Diamondbacks -- while wearing three different uniforms -- since 2011.Justin Upton, on the other hand, hasn't enjoyed facing St. Louis. His .204 career average versus the Cardinals is his lowest against any NL team, though like the rest of the Diamondbacks, he's never faced Kelly.