The Lancaster JetHawks fell behind in the early innings against San Bernardino and never were able to catch up, losing 6-2 in front of 3,178 fans at The Hangar Tuesday night.
Lancaster fell to 17-9 and saw its lead shrink to a half-game over the second-place Stampede (16-9) in the California League's Southern Division.
"Good teams are going to lose," JetHawks center fielder Marcus Sturdivant said. "We're going to have times when we can't come back."
The JetHawks came into the game first in the Cal League in hitting, with a .297 team batting average. But continuing a recent trend, they couldn't do anything against the opposing starter.
San Bernardino starter Keith Sikes retired the first eight hitters and didn't allow a hit until Scot Sealy singled to left with two out in the fifth.
Mike Lanza followed with a bloop single down the right-field line, putting runners on first and third.
Lanza was the only bright spot for the JetHawks offensively, going 2-for-4.
Luis Molina hit a grounder to second that forced Lanza and ended the threat.
"You wait to the fifth and sixth inning to get rolling," Lancaster manager Dave Brundage said, "and you get behind the eight-ball too many times it's going to catch up to you."
Sikes (3-0) left the game after seven shutout innings, giving up three hits, striking out three and walking three.
The Stampede scored three times in the second inning.
With one out, Ervan Wingate singled off Lancaster starter Ivan Montane and advanced to second when Molina bobbled a grounder hit by Scott Richardson.
Matt McCarty drove in Wingate with an RBI single to make it 1-0, and Richardson stole home on the front end of a double steal.
Sealy's throw to second in an attempt to get McCarty went through Jason Cook's legs and into center field, allowing McCarty to go to third.
Matt Carpintier drove in McCarty on a groundout to make it 3-0.
After Montane came back to strike out the side in the third, San Bernardino, which came into the game with a .288 team batting average (second in the league), scored twice more against him in the fourth.
Lancaster broke through in the eighth, putting runners on first and second for Jesus Marquez, who came into the game with a 16-game hitting streak.
But Marquez struck out against left-handed reliever Jake Kenady and went 0-for-4, ending the streak.
After Carlos Villalobos grounded out, Shawn Buhner, who pinch-hit in the seventh, stroked a two-run single to right-center field, cutting into the lead.