(SportsNetwork.com) - Collin McHugh will try to stay unbeaten on the season when he takes the mound Monday for the AL West-leading Houston Astros in the opener of a three-game series against the San Diego Padres.

McHugh has won his first three starts of the season and allowed two runs over his initial two outings. The Astros continued to give McHugh a healthy amount of run support in Tuesday's 6-3 win at Seattle and he allowed three runs in seven innings.

The right-hander's earned run average went up slightly from 1.54 to 2.41 for Houston, which has scored no less than five runs when McHugh pitches. McHugh is 2-0 on the road and will face San Diego for the first time. The Astros are 7-0 in games started by Dallas Keuchel and McHugh.

Houston needed some late-game heroics Sunday to complete a three-game sweep of the Oakland Athletics, as Evan Gattis broke out of an early season slump with a two-run double in the top of the ninth inning. Gattis drove in four runs and Jake Marisnick ended 2-for-4 with a two-run homer and three runs scored.

"I'm glad to finally contribute to a win, to come through with the hit that puts us ahead," Gattis said.

Tony Sipp threw 1 2/3 scoreless innings and Luke Gregerson picked up his first save with a perfect ninth. Asher Wojciechowski lasted just four innings in the start, charged with five runs and five hits.

The Astros are 10-0 when scoring 4-plus runs and have won seven of their last eight games. They are 5-1 on a nine-game road trip and 7-2 away from Minute Maid Park.

San Diego dropped two of three meetings with the Los Angeles Dodgers this weekend to begin a nine-game stay at Petco Park and snapped a four-game slide with Sunday's 3-1 victory.

Brandon Morrow earned his first win of the season (1-0) by holding the rival Dodgers to a run across seven innings with four strikeouts and a walk. Joaquin Benoit relieved Morrow with a scoreless eighth and closer Craig Kimbrel collected his sixth save with two K's in the ninth.

"In these games, against division rivals, the Dodgers, a lot of it is momentum," Padres manager Bud Black said. "A lot of that is from what happens offensively. Obviously Brandon did his part to keep the momentum on our side."

Morrow won for the first time since last April as a member of Toronto. He had been battling injuries the past few seasons.

"I'm healthy now, so it feels good to go out there and pitch good ballgames," Morrow said.

Derek Norris homered and added an RBI double, while Alexi Amarista went deep for the Padres.

San Diego will also host Colorado for three games and hopes James Shields can stay unbeaten when he toes the rubber Monday. Shields is 2-0 with a 3.24 earned run average and did not record a decision in Wednesday's 5-2 loss to the Rockies. He lasted six innings and gave up three runs with a season-high three walks.

Shields had won his previous two outings. The right-hander will make his fifth career start against Houston and is 2-1 with a 1.74 ERA.

The Padres and Astros haven't met since the 2012 campaign. San Diego has won three straight and eight of the last 11 matchups between the clubs.