"Ryan looks good," Roenicke said. "After the first at-bat, he got the base hit the other way, he came back (to the dugout). He said something to me."
While Roenicke wouldn't divulge what that quick conversation was, but he smiled while talking about it.
"I knew," Roenicke said. "I knew he was feeling good."
Braun, who came in on a 2-for-20 slump, singled in a run in the first, hit a solo homer in the fifth -- his third homer of the year -- and doubled in the seventh.
Greinke was also feeling pretty good despite throwing a season-high 115 pitches.
"It was a good game all around," he said. "It was fun. Made a bunch of good pitches. Team played a really good game."
Greinke (2-1) struck out a season-high nine in six solid innings to improve to 13-0 at home with Milwaukee, which won its 10th straight against the Astros.
Greinke was slightly critical of himself, even though he won his first career start at Miller Park against the Astros and kept his streak alive.
In the Houston fifth, after consecutive singles put runners at the corners with nobody out, Greinke struck out Jed Lowrie and J.D. Martinez. Carlos Lee singled to load the bases. Greinke walked Brian Bogusevic to force in a run, then fanned Chris Johnson to end the threat.
"I feel like I really struggled with guys on base," he said. "So, it was really nice to be able to get out of some jams. It definitely wasn't easy out there today."
Greinke allowed eight hits. He walked two but had those three big strikeouts in the fifth when he worked out of a jam.
Since joining the Brewers, the 2009 AL Cy Young Award winner is 13-0 in 18 starts at Miller Park -- the longest home winning streak in the majors.
With the victory, Greinke improved to 3-0 overall against the Astros. He was unbeaten in two starts at Houston last season.
Greinke handed Jose Veras a 6-2 lead to start the seventh, but five of the next six Astros batters reached base. Houston scored three runs on four hits, including Brian Bogusevic's two-run triple, before Veras struck out Jose Altuve and got pinch-hitter Matt Downs to ground out to end the inning.
Lucas Harrell (1-1) took the loss in his first start at Milwaukee and second against Greinke.
Harrell allowed five runs and five hits in five innings.
He said that he got behind a lot today.
"That's something I've been working on and it didn't really work out today," he said. "I got behind a lot and my walks really hurt me. It was just one of those days where I tried to battle."
The 26-year-old right-hander's first career start against the Brewers came Sept. 2 at Minute Maid Park. He went 5 1/3 shutout innings but eventually lost 8-2 to Milwaukee and Greinke, who allowed nine hits and two runs in six innings.
Brandon Lyon took over for Harrell to start the sixth. The first five batters reached base, but the Brewers could only push across one run on a wild pitch.
It could have been worse for Lyon, but Lee and catcher Jason Castro stopped the threat.
With one out and the bases loaded, Rickie Weeks fouled out to Carlos Lee, who caught the ball with his back to the plate. The first baseman turned and fired a strike to Castro, who was blocking the plate. Mat Gamel plowed into him with his left shoulder in a rough collision at the plate, but Castro hung onto the ball to end the inning.
"Carlos did a good job of turning around on the one-hop to him," Astros manager Brad Mills said. "Jason did a good job of grabbing the ball."
And, hanging on to it.
The Astros went ahead in the first on Lowrie's first homer of the season, but the lead didn't last long. Milwaukee moved in front in the bottom half as Braun, Aramis Ramirez and Corey Hart each drove in a run.
Norichika Aoki, who started in center for the slumping Nyjer Morgan, walked, went to second on wild pitch and easily scored on Braun's single. Braun came home on Ramirez's triple. Hart drove in Ramirez with a sacrifice fly.
Gamel tacked on a run for Milwaukee with a sacrifice fly in the fourth.
Greinke also beat the Astros 2-1 in Houston on June 23, 2009, with Kansas City. ... Lowrie's home run was the first allowed by Greinke in 18 innings this season. ... Schafer, whose grand slam helped the Astros rout the Los Angeles Dodgers 12-0 on Sunday, had a tough first at-bat. He fouled a 90 mph fastball off his inner right calf in the first and then spent several minutes walking off the pain. He stayed in the game and doubled the next time he was up.