Happ, who was 12-4 as a rookie for Philadelphia last season, won his third straight start on Sunday in Arizona, as he held the Diamondbacks to a pair of runs and six hits in seven innings, upping his mark on the year to 6-2, while lowering his earned run average to 2.86.
"When I am pounding the strike zone and not walking guys things usually go a lot better for me," said Happ, who was acquired by the Astros as part of the Roy Oswalt deal. "It keeps my pitch count down and lets me have a lot bit more in the tank for when a tough situation comes up. It's definitely nice to get through seven innings."
This will be Happ's first-ever start against the Dodgers, whose struggles continued in the opener of this set on Thursday when Chris Johnson's three-run homer in the sixth inning carried Houston to a 3-2 win.
The Dodgers had jumped out in front on a two-run home run from Andre Ethier in the first inning, but eventually fell for the sixth straight time.
Bud Norris (7-8), who had been winless in his previous three starts, gave up two runs -- one earned -- on three hits over six innings to pick up the win for the Astros, who have won three in a row and five of six.
"The rest of my game was awful," said Johnson, who went 1-for-4 with three strikeouts. "I put Bud [Norris] in a hole in the first inning by making an error, and then [Andre] Ethier hit a homer. Bud pitched well except for that one pitch. I was glad I could do something to help us out after that."
Ted Lilly (8-10) went six frames in the start, giving up three runs on seven hits.
"I didn't get the job done when the game was on the line," Lilly said. "Pitching out of jams is part of what you do. You're not going to win too many games if you can't pitch out of jams."
Heading to the hill for the Dodgers tonight will be righty Hiroki Kuroda, who is 10-12 on the year with a 3.39 ERA. Kuroda absorbed the loss on Sunday against San Francisco, as he allowed three runs and six hits in eight innings.
He beat the Astros the last time he faced them and is 2-0 in four starts versus in this series with a 2.55 ERA.
The Dodgers swept a two-game series from the Astros back in May.