HOUSTON -- Astros general manager Jeff Luhnow hinted more roster moves could be on the horizon in the next few days, especially when the July 31 non-waiver Trade Deadline passes. The Astros have been shuffling players between Minor League affiliates in the last few days because of the trades they've made, and some players could be headed to Houston.

On Wednesday, the Astros promoted pitchers Jose Ciserno, Jarred Cosart and Jake Buchanan to Triple-A Oklahoma City from Double-A Corpus Christi and sent pitcher Paul Clemens to Corpus Christi from Oklahoma City.

"I've talked consistently about early August being a checkpoint for us, as far as our prospects' development," he said. "If we believe a prospect has done everything they need to do at that level and we want to challenge them a level ahead, we're going to go ahead and do that over the month of August. We'll be constrained by who's at what level, but there will be some moves."

Luhnow admitted there are some players performing at Triple-A Oklahoma City who deserve a shot to be evaluated at the Major League level in the same fashion some of the current Astros are getting. Any possible roster moves at the Major League level could be impacted by waivers, however.

Luhnow didn't give specific names, but the players on the roster who are currently out of options are pitchers Wesley Wright and Lucas Harrell and outfielders Brian Bogusevic and Jordan Schafer.

"It's one of the tough decisions we're going to need to make in the next week or two because there are some players that we can't move back to Triple-A without risking losing them," Luhnow said. "So you have to decide carefully how you do that. Not only that, but we have constraints here and positional requirements.

"In an ideal match, we would probably mix and match a bigger group and give everybody an opportunity up here to be evaluated in the last two months. There are realistic constraints that prevent us from doing that as much as we'd like to, but we're going to work around those."

Astros listening, but no longer pursuing deals

HOUSTON -- The Astros, who have pulled off four major trades in the month of July, are no longer actively seeking deals, but the ringer on general manager Jeff Luhnow's phone remains in the on position nevertheless.

"There's still a lot of chatter," Luhnow said. "Obviously, we've been very active. We've been the most active team in baseball, and we feel like we've accomplished a lot and we're going to continue to have dialogues, but we're not stimulating any dialogues. If people call us, we'll listen to what they have to say, but we don't feel like we need to do anything at this point."

The Astros traded veteran first baseman Carlos Lee to the Marlins on July 4 in exchange for a pair of prospects, and they made three deals in a span of five days within the past week that landed Ben Francisco, Francisco Cordero, nine Minor League players and two players to be named.

Houston made a 10-player deal with the Blue Jays on Friday and sent pitchers J.A. Happ, Brandon Lyon and David Carpenter north of the border in exchange for Francisco, Cordero, Minor League pitchers Joe Musgrove, Asher Wojciechowski, David Rollins, catcher Carlos Perez and a player to be named.

On Saturday, the Astros sent Brett Myers to the White Sox for Minor League pitchers Matt Heidenreich and Blair Walters and a player to be named. Veteran starter Wandy Rodriguez was shipped to the Pirates on Tuesday in exchange for Minor League pitchers Rudy Owens and Colton Cain and outfielder Robbie Grossman.

Worth noting

• The Astros called up left-handed reliever Xavier Cedeno from Triple-A Oklahoma City on Wednesday to take the roster spot of Wandy Rodriguez, who was traded to the Pirates. The Astros will announce who is going to start Saturday's game, probably by Friday.