The Miami Marlins attempt to remain in the playoff race as they begin a four-game series against the Arizona Diamondbacks on Thursday. The Marlins' postseason aspirations took a hit Wednesday as they dropped a 5-2 decision to St. Louis, preventing them from completing their first three-game sweep of the Cardinals since 1996. With the loss, Miami fell seven games behind first-place Washington in the National League East and 4 1/2 in back of St. Louis for the second wild card.Jeff Baker kept the Marlins from being shut out with a pinch-hit, two-run homer in the ninth inning, but Miami went on to fall to 2-1 on its nine-game homestand. Arizona began its 10-game road trip by splitting a doubleheader at Cleveland on Wednesday. Randall Delgado took the loss in the opener by serving up rookie Zach Walters' first career homer - a walk-off solo shot with one out. The right-handed reliever redeemed himself in the nightcap, notching the victory by retiring three straight batters after allowing a leadoff double in the 11th inning.TV: 7:10 p.m. ET, MLB Network, FSN Arizona, FSN Florida (Miami)PITCHING MATCHUP: Diamondbacks RH Chase Anderson (7-4, 3.06 ERA) vs. Marlins RH Brad Penny (1-0, 1.80)Anderson continued his strong pitching Friday, limiting Colorado to one run and four hits over six innings in a 5-3 victory. The 26-year-old has allowed two runs or fewer in each of his last five starts, going 2-0 with a 1.74 ERA in that span. Anderson won his only career outing against Miami on July 7, allowing one run and seven hits in six frames.Penny made his first major-league appearance since 2012 on Saturday and was impressive, allowing two runs - one earned - and four hits in five innings of a 4-3 victory at Cincinnati. The 36-year-old had his contract purchased from Triple-A New Orleans, where he went 2-2 with a 2.28 ERA in five starts. Penny has been superb against Arizona over his career, going 10-3 with a 1.97 ERA in 23 games - 19 starts.WALK-OFFS1. Diamondbacks OF Ender Inciarte is riding a 13-game hitting streak and is 16-for-50 in 11 contests this month.2. Miami 3B Casey McGehee has hit safely in seven straight games and recorded multiple hits in five of his last six contests.3. The Marlins are expected to activate RHP Henderson Alvarez (shoulder) from the disabled list to start Saturday's game.PREDICTION: Diamondbacks 8, Marlins 2