PITTSBURGH -- Yasmani Grandal hit one of three Los Angeles homers Thursday, but he was more impressed with starter Hyun-Jin Ryu's performance in a 5-2 win over the Pittsburgh Pirates at PNC Park that gave the Dodgers 90 wins.

"He attacked the zone, started pitching in the strike zone and all of a sudden he's into the sixth inning and cruising," Grandal said. "I think we've seen a couple of things from him, from the beginning of the year till now, that allowed him to get to where he's at right now. It's allowed him to go longer in the outing.

"Later in the game he's still throwing his best pitches and I think he's just going to get stronger from here on out."

Ryu (5-6) remained undefeated in his past nine starts, a stretch in which he is 3-0. He gave up one run and four hits in six innings.

"My second half of the season, I'm getting a feel for the game, commanding more pitches. I still have some things to work on," Ryu said. "I think I've developed my command a little bit more so I can pitch six or seven innings."

Brandon Morrow pitched a perfect ninth for his first save since May 10, 2009.

Curtis Granderson and Adrian Gonzalez also hit solo homers as Los Angeles became the fastest team in franchise history to reach 90 wins.

A day after Rich Hill flirted with a perfect game and lost a no-hitter on the Pirates' walk-off win in the 10th, the Dodgers (90-36) avoided much drama, avoided losing back-to-back games for the first time since July 21-22 and became the first team to 90 wins this season.

Pittsburgh (61-67) has lost nine of its past 12.

Pittsburgh starter Chad Kuhl (6-9) was trying try to bounce back from his worst start of the season, but again struggled. He gave up two runs and six hits in four innings, with five walks and two strikeouts, needing 93 pitches -- the same as Ryu, but in two fewer innings.

"Had some rough innings where the pitch count got up. Misfiring. Didn't get some calls," said Kuhl, who was visibly agitated about his pitches. "They were everywhere. Out, up, in. Just really bad. A lot of missed calls, and then misfires from me."

Kuhl got out of a bases-loaded, one-out jam in the first when he struck out Gonzalez and Yasiel Puig, although he needed 28 pitches in the inning.

He pushed hit pitch count to 63 through two innings, and the Dodgers took a 1-0 lead on Chris Taylor's two-out RBI single.

Pittsburgh tied it 1-1 in the bottom of the second on Jordy Mercer's two-out RBI single.

Granderson pushed Los Angeles to a 2-1 lead with a towering two-out homer in the fourth down the right-field line that cleared the stands and bounced into the Allegheny River.

That gave Granderson nine homers in August and three in six games since joining the Dodgers.

Los Angeles made it 3-1 in the seven on another two-out RBI when Enrique Hernandez singled.

Adam Frazier's RBI double off former Pittsburgh left-hander Tony Watson closed it to 3-2 for the Pirates in the seventh.

Grandal and Gonzalez increased it to 5-2 with one-out solo homers in the eighth.

"I missed a lot of (hits) earlier in the series," Grandal said.

The two homers came on consecutive pitches off of reliever Angel Sanchez, who entered at the top of the inning for his major league debut. It was Gonzalez's 100th homer as a Dodger.

"I was probably a little too excited, missing some pitches," Sanchez said. "They got a good swing on it."

It was something the Dodgers didn't do with great proficiency. They pounded out 14 hits but stranded 15 runners.

"I think that at times we could probably put forth a batter at-bat, but there are other times in those situations we might line out and not cash in," manager Dave Roberts said. "For us, it's more about having that quality at-bat. You can always get better."

NOTES: Pittsburgh manager Clint Hurdle was ejected by plate umpire Paul Emmel in the seventh after arguing a pitch call. ... Pittsburgh C Francisco Cervelli (left wrist inflammation) was eligible to come off DL but did not. ... Pittsburgh is working to get 3B Jung Ho Kang (in South Korea after DUI charge) to winter ball in the Dominican Republic, according to multiple reports. ... Los Angeles returns home for three games against Milwaukee before hitting the road again. ... Pittsburgh embarks on a six-game road trip, the first of 28 straight games against National League Central clubs. ... After Pittsburgh and St. Louis played in MLB Little League Classic on Sunday, Little League World Series teams from Italy, Venezuela and Japan attended Thursday's game.