Shields does his part with 12 strikeouts against Astros

SAN DIEGO -- James Shields wasn't impressed much with the season-high 12 strikeouts he compiled in six innings Monday night against the Astros.

"I'm not too worried about strikeouts in my game, I'm worried about winning," he said. "It's my job to keep us in a game and give us a chance to win every night."

Shields did just that, as he allowed one earned run. He was long gone by the time the bullpen fizzled, allowing the Astros six runs in the final three innings of a 9-4 Padres loss at Petco Park.

Shields, who in February signed the largest contract in club history (four years, $75 million), has been everything the Padres hoped for. After five starts, he has a 2.90 ERA, leads baseball in strikeouts (41) and has kept his team in every game.

On Monday night, he helped the Padres with his arm -- and his bat and feet.

Shields had an infield single that prolonged a three-run fifth inning. He even scored from first base as Wil Myers doubled in two runs to pull the Padres within one.

Video: HOU@SD: Shields helps himself with an infield hit

In the sixth inning, after the Padres had tied the game at 3-3, Shields allowed a leadoff double to Jed Lowrie, who had gotten him for a home run in the fourth. But the Padres ace retired the next three batters he faced, two with strikeouts, to finish strong.

"I felt I was locating in certain situations, for the most part," he said. "There, in the sixth inning, it was crucial to get those two strikeouts."

Catcher Derek Norris was impressed with what Shields accomplished.

"He was working with a tight [strike] zone, which was more impressive," Norris said. "He threw the ball well."

Shields used 111 pitches to get through six nnings. An error by shortstop Alexi Amarista in the fifth, when he dropped a throw from Norris on Jake Marisnick's stolen base, extended his outing.

"The one Amarista had but [Marisnick] kicked it out of his glove, I think I threw 15 pitches after that," Shields said, adding that high strikeout totals also lead to high pitch counts.

The 12 strikeouts were the most by Shields since April 17, 2014, when he also had 12 against the Astros while pitching for the Royals.