HOUSTON -- Luis Durango was optioned to Triple-A Oklahoma City following the Astros' 5-4 win on Wednesday night over the Reds.

The Astros will announce a corresponding roster move on Friday.

"We're going to see what we have coming up," said manager Brad Mills.

Durango, who was called up from Oklahoma City on Sunday, made his Astros debut on Monday. He drove in his first run as an Astro on a single in the fifth inning of Tuesday's game.

Martinez becomes Astros' latest No. 3 hitter

HOUSTON -- J.D. Martinez became the third different Astro to occupy the No. 3 spot in the batting order during Houston's series against the Reds, as the youngster was slotted into the three-hole for the first time in his brief Major League career on Wednesday night.

Martinez, who was recently named the Texas League Player of the Month for July after hitting .380 with seven home runs and 16 RBIs in 26 games last month at Double-A Corpus Christi, said changes are happening quickly, but he welcomes all the new tasks. He homered in his first at-bat on Wednesday, launching a 2-2 pitch over the left-field wall for his first Major League home run.

"You're here two days ago, and now you're hitting third, and it's just like, 'Woah,'" Martinez said. "But I'm up for the challenge, and I love the challenge. I like to be challenged."

Manager Brad Mills said the speedy jump to the big leagues can be overwhelming for the Astros who were called up from Double-A. But it's a great experience to be able to play at the Major League level at such a young age.

"There might be a couple guys that are a little bit, kind of still, wide-eyed a little bit," Mills said. "But that'll come, and that's OK, too. There's nothing wrong with that. That's part of developing and part of the process."

Mills said Jason Bourgeois, who hit leadoff on Wednesday, wanted the scorecard after hitting third for the first time as Major Leaguer at the end of July.

"I think that kind of leads you to understand he's probably more comfortable hitting leadoff, because he's done that," Mills said.

Martinez ended Wednesday's game 3-for-4 with four RBIs, including a go-ahead, two-run double that helped Jordan Lyles capture his first Major League win.

Mills: Astros' relievers getting job done

HOUSTON -- Manager Brad Mills said the best thing about the Astros' bullpen is that it's finally piecing together solid outings.

The 'pen threw nine scoreless innings in the first two games of the Reds series. Fernando Rodriguez threw a scoreless eighth inning in Wednesday night's series finale, before Mark Melancon allowed one run in the ninth. Melancon still saved the game, forcing Miguel Cairo to fly out to preserve Jordan Lyles' first career Major League win.

Mills said the addition of Doug Brocail as the pitching coach may be producing a positive effect on the relievers.

"I'm sure he has a lot of experience that they can draw off of, and I'm sure he's probably shared some of that experience with them -- without even knowing he's sharing that experience with them -- which has helped," he said.

Schafer eager to join Astros on field

HOUSTON -- Jordan Schafer said it's frustrating not to be able to get on the field after being traded from the Braves to the Astros in the Michael Bourn deal. He's still about a week or two away from returning, after injuring his left middle finger in a game on July 26.

"It just takes time," Schafer said. "The exercises help a little bit. But there's not really much you can do to speed up the process. It's just going to take some downtime, and hopefully it'll be all right here shortly."

He said it's a slow-healing injury, but he can feel noticeable progression in the healing process every three or four days.

"It's pretty much day by day, right now, seeing how I feel," Schafer said. "Hopefully here shortly, I'll be able to start swinging off the tee a little bit."

Worth noting

• Mills said the Astros won't be seeing the same power-throwing Dontrelle Willis on Wednesday night that they were accustomed to in past seasons.

"Now, he's a little bit more of a finesse type and a control-type pitcher," Mills said. "He doesn't have that leg kick like he used to, and body turn and everything else."

• Pitcher Jarred Cosart, who was acquired in the Hunter Pence trade, allowed just two hits in six shutout innings on Tuesday night in his first start at Double-A Corpus Christi. Jonathan Singleton, also acquired in the Pence deal, is 5-for-11 with a home run in three games at Class A Lancaster.