(Sports Network) - The NL West-leading Arizona Diamondbacks are finally back at the .500 mark and will try to maintain their division lead tonight, when they open a three-game series versus the San Diego Padres at Chase Field.

Arizona sits just 1 1/2 games ahead of the Los Angeles Dodgers in the West, and just split a four-game series with the Milwaukee Brewers. The DBacks ended a two-game slide with Thursdays dramatic 6-5 victory in the series finale, as they rallied for six runs in the ninth to record the win.

Conor Jackson's two-run single capped the comeback and Chad Tracy had a pinch- hit three-run triple in the frame for Arizona, which had dropped six of eight entering the game and put the brakes on a two-game slide.

Arizona sent seven hitters to the plate and made a winner of Leo Rosales, who pitched a scoreless inning of relief. Starter Brandon Webb was in line for the loss after giving up five runs on nine hits in six innings, but was bailed out at the last moment.

The Diamondbacks will send Dan Haren to the hill on July 4th, and the right- hander is 8-4 with a 2.85 ERA in 17 starts this season. Haren is unbeaten (3-0) in his last six starts, with Arizona going 5-1 over that stretch. In his last outing on June 29 at Florida, Haren gave up just one unearned run in seven innings of a 4-3 loss for the no-decision. He fanned seven batters and issued a pair of walks.

The right-hander has been solid at home this season, sporting a 7-1 mark with a 2.41 earned run average in nine trips to the Chase Field mound. Haren is also holding the opposition to a .206 batting average in the friendly confines.

Haren is 1-0 with a 1.17 ERA in four career games, three of which have been starts, against San Diego. He needs four more strikeouts to post 100 for the fourth consecutive season.

San Diego has lost two straight, 10 of 11 and 14 of its last 16 games, including Wednesdays 8-1 loss to the Colorado Rockies in the finale of a three-game set at Coors Field. Starter Randy Wolf lost his fourth consecutive outing, throwing only four innings and giving up seven runs on six hits with four strikeouts and four walks.

Brian Giles batted 2-for-4 and Chase Headley added his fourth home run of the season for San Diego, which has dropped six consecutive series. The Padres are last in the NL West standings, 10 games back of Arizona.

Cha Seung Baek gets the nod tonight for the Padres, and he is 1-4 with a 5.43 ERA in six games (five starts) this season. Baek is 0-3 in his previous five trips to the hill, having lost back-to-back starts. In his last outing on June 28 versus Seattle, Baek was reached for four runs and eight hits through five innings of a 4-2 setback.

The right-hander has never faced Arizona.

Arizona has won four of its six matchups with the Padres this season.