Opposite dugout: Underachieving Diamondbacks heating up after slow start

Manager: Kirk Gibson, fifth year Record: 15-25 Last 10 games: 7-3 Who to watch: 1B Paul Goldschmidt (.321/.371/.531, 7 HR, 23 RBIs); C Miguel Montero (.287/.389/.457, 5 HR, 22 RBIs); RHP Josh Collmenter (1-2, 3.44 ERA); RHP Bronson Arroyo (3-2, 4.89 ERA) Season series vs. Nats (2013): 2-4, 17 runs scored, 24 runs allowed Pitching probables May 12: Josh Collmenter vs. Jordan Zimmermann, 9:30 p.m., MASN2 HD May 13: Bronson Arroyo vs. Stephen Strasburg, 9:30 p.m., MASN2 HD May 14: Brandon McCarthy vs. Doug Fister, 3:30 p.m., MASN HD Series breakdown The Diamondbacks have endured their share of bad fortune. Pitching injuries galore have contributed to Arizona starting 15-25 for the second-worst record in the National League. But that record doesn't reflect how well the D-backs have played lately. The NL West's cellar-dwellers have have won four of five and seven of 10 heading into a home series with the Nationals, which begins tonight at Chase Field. The D-backs have struck a balance over the last 10 games to heat up a bit after starting 8-22, scoring at least three runs in nine of the last 10 contests and permitting more than four only three times. But that hasn't helped Arizona climb the pitching rankings, as the team ranks last in the NL with a 4.81 ERA despite a rotation that has at times included Bronson Arroyo, Wade Miley, Trevor Cahill and Brandon McCarthy. The pitching staff has taken quite a hit over the last year with Tommy John surgery seeming contagious in the D-backs clubhouse. Daniel Hudson has undergone the procedure twice since 2012 while both Patrick Corbin and David Hernandez have needed elbow ligament replacement surgery this year. Corbin led Arizona starters with 14 wins and a 3.41 ERA last season while Hudson won 16 games in 2011, his last full season. But there was still plenty of quality depth left, and it has underperformed. Josh Collmenter is the only starter to post an ERA under 4.82 so far this year. Miley (4.82 ERA), Arroyo (4.89 ERA), McCarthy (5.66 ERA) and Cahill (6.12 ERA) have all struggled, with Cahill losing his starting job. The Nats will see Collmenter (3.44 ERA) in the first game of the series, as he'll face Jordan Zimmermann tonight. Arroyo and McCarthy pitch in the last two games of the set. The D-backs' offense has done a fine job, ranking fourth in the NL with a .252 average and sixth with 151 runs. First baseman Paul Goldschmidt, catcher Miguel Montero and center fielder A.J. Pollock have all hit well so far while right fielder Mark Trumbo, the D-backs' biggest offseason acquisition, is out with a stress fracture in his left foot. Goldschmidt is leading the way in most categories with a .321 average, .902 OPS, seven homers, 13 doubles and 23 RBIs. Montero has an .846 OPS and 22 RBIs. Pollock has an .806 OPS. Despite their overall record, the D-backs are playing much better lately, which could be bad news for a Nats team that was just swept by the A's.