HOUSTON -- Angels manager Mike Scioscia called what Houston starter Bud Norris has done to his team this year a "nightmare you can't shake."
Pinch-runner Peter Bourjos scored the go-ahead run in the eighth on an error and Erick Aybar added a two-run single in the ninth to help the Angels to the victory.
Hank Conger doubled off Paul Clemens (4-3) to start the eighth. Conger was replaced by Bourjos before Aybar drew a walk. Bourjos took third on a fly out by J.B. Shuck. Shortstop Ronny Cedeno's error on the play, when he bounced the ball trying to pick off Aybar at second, allowed Bourjos to dash home just ahead of the throw.
Aybar's bases-loaded single sent two home and extended the lead to 4-1 in the ninth.
Houston's Jason Castro homered in the fourth before Mike Trout tied it at 1 with an RBI single in the sixth.
The Angels had scored 33 runs on 46 hits in their last four games. But Norris, who entered the game having allowed just one run in three starts -- all wins -- against Los Angeles this season, continued to be tough on the Angels. He yielded four hits and no earned runs with five strikeouts in seven innings.
"He's thrown as well as anybody we've faced this year, probably better than anybody we've faced on a consistent basis," Scioscia said. "He's got that fastball that's sneaky and he's mixing his breaking ball in. I thought we had better at-bats against him tonight but the results were pretty much what we've seen the first several times he's pitched against us."
Conger was glad they were finally able to win a game against the Astros when Norris was pitching and extend their winning streak to four games.
"It's huge," he said. "Just the fact that we were able to pull off a win facing Bud Norris, knowing how well he's been throwing against us. That was one that we really needed coming off the road trip with Detroit and bringing that momentum here was really huge for us."
Los Angeles starter Jerome Williams limited Houston to five hits and a run over 6 1/3 innings. Dane De La Rosa (3-1) and Kevin Jepsen pitched 1 2/3 scoreless innings before Ernesto Frieri allowed one run in the ninth for his 20th save.
The win by Los Angeles breaks a four-game losing streak to the Astros, but the Angels still trail Houston 7-4 this season.
Houston manager Bo Porter was disappointed with the two errors his team made that led to two runs. The Astros lead the majors with 63 errors this season.
"We've all played this game and understand that mistakes do happen and errors are a part of the game," he said. "For the most part it's the speed of the game and the mental part that we definitely need to clean up."
Houston had several chances to add to its run total. Perhaps the best opportunity came in the eighth inning. Jose Altuve walked with one out and stole second base. A single by Brett Wallace sent him to third but Jepsen retired Castro and Chris Carter to end the threat.
Castro opened Houston's fourth with his homer to the bullpen in right-center to make it 1-0. Williams got back on track after that, retiring the next three batters. Cedeno walked with no outs in the fifth, but Williams still faced the minimum in that inning when Cedeno was thrown out trying to steal second on a strikeout by Barnes.
Aybar started the sixth with a single and advanced to second on an error by Brandon Barnes. A one-out single by Trout sent Aybar home to tie it at 1-1.
Altuve singled in the sixth before Castro took a one-out walk. But Houston came away empty-handed when Altuve was caught trying to steal third before Carter grounded into a force out.
Carlos Pena and J.D. Martinez hit back-to-back singles to start the seventh and chase Williams. Pena was thrown out trying to advance to third on the single by Martinez.
De La Rosa struck out Cedeno before center fielder Trout made an excellent running catch on a sharp fly ball hit by Matt Dominguez to end the inning.
Barnes made a pair of nifty defensive plays in the third inning. The first one came when he sprinted and leaped to grab a fly ball hit by Conger before crashing into the padded wall in center field and falling to the ground for the first out of the third.
He then ended the inning by dashing to make a diving catch on a liner hit by Shuck.
Scioscia was impressed by Conger's at-bats on Friday.
"Hank hit the ball hard every time," Scioscia said. "Drove the ball well to center field; Barnes made a couple good plays on him. And then he just hammered that last one for a double in the eighth and was the start of our go-ahead rally."
The series continues on Saturday when Houston's Jordan Lyles opposes Joe Blanton. ... Houston signed ninth-round draft pick C catcher Brian Holberton, 14th-rounder LHP Chris Cotton, 18th-round pick 3B Adam Nelubowich, 19th-round pick C Jake Rodriguez and RHP Juan Santos, who was selected in the 39th round.