HOUSTON -- There is finally a light at the end of the tunnel for Astros outfielder Jordan Schafer.

Schafer, who has been on the 15-day disabled since July 20 with a left middle finger joint injury, is scheduled to fly to Oklahoma City on Wednesday to begin a five-game rehab assignment with the Triple-A RedHawks. Schafer took batting practice on the field Tuesday and was examined by Dr. Tom Mehlhoff.

"It's hard enough getting traded when you're on the DL," said Schafer, acquired from the Braves in the Michael Bourn deal on July 31. "To not really know anybody, and come over and feel like you want to get out there and prove to your teammates you can play, I'm excited to get out there."

If all goes well, Schafer will fly to Denver on Sunday night and be activated prior to the Astros' game Monday against the Rockies. He was hitting .240 with 15 stolen bases in 52 games in center field with the Braves before being traded.

"It's been 18, 19 days since I played," Schafer said. "Obviously, I'm anxious to get out there, especially with a new team. I'm ready to get out there and start playing and see what I can do."

Quintero back behind plate despite ailments

HOUSTON -- Perhaps one of the toughest players the Astros have had in their clubhouse in recent years, catcher Humberto Quintero was in Tuesday's lineup despite a variety of ailments.

Quintero, who had his 11-game hitting streak snapped in Monday's 4-3 loss to the Cubs, underwent an MRI on his knees and back on Tuesday and was given a green light to play. He said the tests showed that a disk in his back was inflamed, and he's scheduled to have a cortisone injection after Wednesday's game.

"Everything is fine," said Quintero, typically downplaying his lingering health concerns.

Quintero entered Tuesday having hit safely in 16 of his past 18 games with an at-bat. It would have been difficult to keep him out of the starting lineup, considering he's had a terrific working relationship the past two years with starter Brett Myers.

Speedy Astros get in extra bunting work

HOUSTON -- Jason Bourgeois, J.B. Shuck, Jose Altuve and Jimmy Paredes -- four of the fastest players on the Astros -- were at Minute Maid Park four hours prior to first pitch Tuesday for extra bunting work.

"It's something we've got to do," Bourgeois said. "I need to make sure I can do it myself, sacrificing and bunting for base hits. When the hits don't come, you have to break out all the tools. Sometimes it's tough, especially when you have the third baseman breathing down your throat. It's something I definitely need to use more frequently."

Altuve, who hit a combined .389 between Class A Lancaster and Double-A Corpus Christi this year, wasn't asked to bunt often in the Minor Leagues. That hasn't been the case since he joined the Astros, where he's hit second in the order.

"We're trying to incorporate that into his game, to be able to move runners along for other guys to be able to drive runs in," said Houston manager Brad Mills. "We want him to drive in runs as well, but if we can set him up to have some big innings, we want to be able to take advantage of it."

Scout who signed Martinez pays a visit

HOUSTON -- The scout who signed J.D. Martinez out of Nova Southeastern University in Davie, Fla., paid a visit to Minute Maid Park on Tuesday to meet up with the Astros' outfielder, who's become Houston's No. 3 hitter since he was called up to replace Hunter Pence last month.

Greg Brown is he head coach at Martinez's alma mater, which only strengthens his bond with the 23-year-old Florida native.

"He's the first guy I ever signed," Brown said. "The accomplishments he's had, especially the road he's gone from being drafted in the 20th round, he's done nothing but hit, and I'm very proud of him. It's all him, and I'm sitting here enjoying it."

Brown said Martinez was a pretty well-known prospect in scouting circles in south Florida, which is a hotbed of baseball talent. He was drafted in the 36th round out of high school by Minnesota in 2006, but didn't sign. The Astros were thrilled to get him three years later.

"It was just a situation where [assistant general manager of scouting] Bobby Heck did a great job knowing when we could get him," Brown said. "We took him where we were comfortable taking him. As far as my feelings for him, I felt he was a top-of-the-Draft-type player and a big leaguer. Obviously, he has the beginnings of a good career, and I'm excited to watch him grow."

Worth noting

• Chris Johnson could return to the lineup for Triple-A Oklahoma City as early as Wednesday after sitting out since Friday, when he was hit by a pitch just above the left wrist and had to leave the game. X-rays were negative, and he took batting practice for the first time Tuesday. He's hitting .273 with one homer and eight RBIs in nine games with the RedHawks.

• Jimmy Paredes was back in the lineup Tuesday at third base after being given a day off on Monday. Manager Brad Mills said he needs to give rookies like Paredes a few days off here and there, considering they're probably in the midst of their longest professional season. "For a lot of these guys, they haven't played in September in their professional career, and we're going to monitor that," Mills said.