HOUSTON -- Two of Zack Greinke’s biggest takeaways from his debut in an Astros were a result of his new team’s blistering offense: The locomotive above left field makes a lot of noise, and there’s a long wait between innings when he’s not pitching.

That’s because the Astros erupted for four home runs, including two by American League Player of the Month for July Yuli Gurriel, and scored runs in six of the eight innings they batted in to blast past the Rockies, 11-6, on Tuesday night for their 15th win in their past 18 games.

The largest crowd of the season at Minute Maid Park was eager to see the six-time All-Star and former American League Cy Young Award winner ease into a rotation that’s been on a terrific run for the last three weeks. Greinke, traded from the D-backs on Wednesday, provided mixed results, battling his fastball command while giving up five runs in six innings, but he picked up the win to improve to 11-4.

“I thought he pitched his way in and out of traffic quite a bit,” Astros manager AJ Hinch said. “He just couldn't quite get out of the last inning with the one breaking ball that cost him a three-run homer. Not having been around him, I was impressed with how he goes about his business, how he prepares, how he worked his way through his outing. He was very calm and very interactive during the game.”

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The first two hitters Greinke faced in the fourth inning reached on an infield hit and a walk, and both scored to cut Houston’s lead to 3-2. The Astros led, 5-2, in the sixth when Raimel Tapia hit a two-out, three-run homer to tie the game on a 66-mph curveball -- only the second hit Greinke has allowed this year on a sub-70-mph pitch. Greinke retired the next batter, Yonder Alonso, on a lineout to end his outing.

“I usually locate that pitch really good,” Greinke said, “so I don't know why I threw that one so bad.”

The Astros pounded the Rockies' bullpen, taking a 7-5 lead in the sixth inning on a solo homer by Carlos Correa and an RBI single by George Springer. Houston then added four runs in the seventh on a two-run double by Correa and two-run homer by Gurriel, making it 11-6.

“We never really give a team an inning to breathe,” Hinch said. “When we’re right, and we’ve been right a lot lately, we put a lot of pressure on you from the very beginning. I thought our baserunning was very good tonight, but our at-bats have been really good and synced up together.”

Hinch was impressed with Greinke’s intellect and preparation, but the Astros skipper admitted it will take him a while to figure out the enigmatic pitcher’s mannerisms, cues and fatigue levels.

“He was pretty much flat-line emotion as you would imagine,” Hinch said. "That’s the way he rolls. I love it.”

This was the fifth time this season Greinke had faced the Rockies -- the previous four coming when he played for the D-backs. Rockies designated hitter Daniel Murphy said facing Greinke brings challenges.

"For me personally, I enjoy facing Zack,” Murphy said. “Not because I think I'm going to have success, but because he plays chess out there. I kind of like that. I looked at [the schedule] and saw it and said, ‘Oh, how unique that he goes to a completely different league, and we're going to see him his first start.’”

Greinke lamented his rotten fastball command, saying his 99-pitch outing was OK but not great. He said he didn’t feel awkward joining a new team like he has in the past.

Nothing will put you at ease like the kind of run support the Astros’ deep lineup provided on Tuesday, with Gurriel hitting his 16th and 17th homers since June 23, Correa going 2-for-4 with three RBIs and Michael Brantley going 2-for-5 for his 44th multihit game of the season. A two-run homer by rookie Yordan Alvarez in the second, which traveled a Statcast-projected 436 feet into the upper deck in right field, gave him a team-record 14 homers in his first 42 games.

Greinke, a pretty good hitter in his own right, watched the onslaught from the bench and marveled how often the train was blaring its horn every time the Astros scored.

“I was telling [catcher Martin Maldonado] that it kind of reminds me when I was back in Milwaukee and it seemed like we scored, like, 10 runs a game,” Greinke said. “It’s a good offense, and it’s fun to pitch with that going on.”