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The San Diego Padres suddenly find themselves in the thick of a hunt for first place in the NL West.

The Padres will try to cut into their deficit for that top spot again on Saturday night as they eye a fifth straight victory in the middle portion of a three-game series with the division-leading Arizona Diamondbacks.

Following a three-game sweep of the NL East-leading Atlanta Braves, San Diego notched its third four-game winning streak of the season by taking Friday's opener 2-1 thanks to a gem by Eric Stults. His first complete game since 2009 helped the Padres put their 5-15 start even further behind them.

Stults gave up just two hits in his third career complete game. The first came on Gerardo Parra's leadoff double and he would later score in the inning on a Cody Ross sac fly.

However, Arizona would not get another hit until there was one out in the ninth inning and drew just one walk off Stults in the game. The San Diego hurler retired 16 of his final 17 batters while also coming up with some key plays in the field.

"I thought it was a masterful performance," Padres manager Bud Black said. "He was outstanding, the mix of pitches. The wide range of velocities keeps the hitter off balance and disrupts their timing."

Stults effort was nearly wasted until Logan Forsythe came through with a two- run single in the sixth inning with two outs. That allowed San Diego to pull within four games of Arizona for first place in the division.

Friday's win gave San Diego a 4-3 edge in the season series so far and a win tonight would put the Padres at .500 for the first time this season.

San Diego didn't do much against Arizona starter Trevor Cahill until Forsythe's go-ahead hit. Cahill matched a career high with 10 strikeouts, logging 5 2/3 innings and losing his fourth straight decision.

"He was pretty darn good. It was just the sixth. You can't fault anybody for one inning or one hitter," Arizona acting manager Alan Trammell said after his club lost for the fourth time in six games.

Trammell was managing in place of Kirk Gibson, who served a one-game suspension for the on-field incidents that occurred during Tuesday's game with the Los Angeles Dodgers.

Gibson was punished with the ban after Ian Kennedy hit Dodgers pitcher Zack Greinke with a pitch up high in the shoulder/head area after both benches had already been warned. The benches emptied and several skirmishes broke out on the field.

Kennedy was hit with a 10-game suspension, while infielder Eric Hinske received a five-game ban for what the league called aggressive actions during the incidents. Both players are appealing, meaning Kennedy is still scheduled to pitch Sunday's finale.

Kennedy was originally scheduled to oppose Jason Marquis, but the Padres altered their rotation on Friday. Marquis will move up a day to pitch tonight, with Clayton Richard sliding back to Sunday. Marquis will still be on regular rest because of Thursday's off day.

It makes sense for Black to try and maximize Marquis' appearances given that the right-hander is 8-2 with a 3.59 earned run average this season and has won seven straight decisions.

Marquis is unbeaten over his last nine outings, posting a 3.15 ERA in that span, and won his second straight start on Monday. The 34-year-old held Atlanta to a pair of runs over 7 2/3 innings on five hits and a season high- tying five walks.

"I allow the game to dictate how I attack it," Marquis said. "I go in with a game plan, but I just see where the game takes me."

Still, the walks could be an issue. Marquis had issued at least four free passes in nine of his 13 starts this year, with an MLB-leading 43 total over 77 2/3 innings.

Marquis is 3-7 with a 4.53 ERA in 17 career meetings with Arizona, all but one of those starts. He has a 6.75 ERA in two encounters this season, though he did hold the Diamondbacks to three runs over six frames of a home victory on May 3.

Wade Miley hopes to end his season-long struggles against the Padres tonight as he makes his 14th start of the campaign for the Diamondbacks.

Miley has lost both of his starts versus San Diego this season, allowing 11 runs over 8 2/3 total innings for an 11.42 ERA. That has dropped his career numbers in this series to 1-4 with a 7.52 ERA in six meetings.

The 26-year-old southpaw is 1-0 over his last two starts -- on the road versus St. Louis and Los Angeles -- despite allowing six runs and 20 hits over 12 2/3 frames. It has been an improvement over his previous four outings, an 0-4 span that saw Miley pitch to a 9.14 ERA.

Miley is 4-5 on the season with a 4.89 ERA.