HOUSTON -- Describing his right ankle as "more sore" a day after rolling it while running in the indoor batting cage, David Freese said he does not expect to play during the rest of the Cardinals' series against the Astros.

Whether Freese will miss more time than that remains too tough to forecast right now.

"Motion is all right. I'm still working on that," Freese said. "I'm walking around all right. I got it pretty good. Nowadays, you can take care of a sprain pretty quickly. We're just getting after it."

Freese sat out of batting practice on Tuesday and focused only on his arms during his pregame workout.

"I'm not going to push it at all," he said.

Freese has a history of ankle troubles, though this is not nearly as serious as the two previous incidents which required surgery. X-rays taken on Freese's right ankle confirmed that there is no fracture.

Until Freese is cleared to return to the field, Matt Carpenter will get regular starts at third. The Cardinals will, however, be more aggressive in getting Freese back into the lineup than they might have been earlier in the season.

"Right now, when guys can go, we're going to go," manager Mike Matheny said. "We're going to push it all the time. We have to. It's not like we have a lot of time to sit and have guys get better."

Chambers offers Cards speed off the bench

HOUSTON -- Adron Chambers talks openly about trying to make a long-term fit for himself in St. Louis. And he has a clear idea of what niche is his to latch onto.

A Cardinals team not built with basestealers could have one in Chambers, who made the craft a focal point of his work this season. Chambers swiped his first career base on Saturday as a pinch-runner in the ninth inning. He has been manager Mike Matheny's top pinch-running option, and, as was the case on Saturday, Chambers usually enters with a green light to steal if he sees an opening.

Chambers' education in basestealing has been aided by past and current players. He has talked extensively with former Cardinals Lou Brock and Willie McGee about the craft. He's listened to Juan Pierre and Dee Gordon share lessons learned through their experience. He's even picked the brain of infield coach Jose Oquendo, who has given Chambers insight into what middle infielders anticipate during a steal situation.

All that advice has ranged from learning when to stretch a lead to zeroing in on the crease of a pitcher's pants, as that gives away when he's in motion to the plate.

"There were so many things that I was able to grasp," Chambers said. "Now, for me, it's just doing it on the field. When I started seeing guys like Yadier Molina throwing it to second base with ease I knew I couldn't rely only on speed.

"I am finding my ability, what I bring to the team. Basestealing is one thing. When they say my name, I want them to think about stolen bases."

Chambers has started only six games for the Cardinals in 2012, but he has appeared in 37 of the team's 47 games played while he was on the roster. Chambers has a legitimate chance at being included on a postseason roster because of the speed he would offer off the bench.

"He's really improved in almost every facet. He really has," Matheny said. "Even his arm, you don't usually see improvement when you get to this level. But his arm, his jumps, he had a strong season in Triple-A, showed some power. He's really impressed us."

Freeman has become Cards' go-to lefty

HOUSTON -- Marc Rzepczynski is the only left-handed reliever the Cardinals have had on their roster for the entire season. He has, however, hardly had a presence out of the 'pen this month, one in which St. Louis has overworked several other members of the bullpen.

Rzepczynski, traded to the Cardinals in July 2011, was expected to assume a late-inning lefty specialist role this season, his last before becoming arbitration eligible. He served in such a capacity early in the year, but has since lost opportunities.

Part of that is due to how the Cardinals have lined up the back of their bullpen. With Edward Mujica, Mitchell Boggs and Jason Motte emerging as the team's go-to trio for the seventh, eighth and ninth, manager Mike Matheny has hardly called upon Rzepczynski for matchup situations in those frames.

But Rzepczynski hasn't recently been given many chances in the earlier innings either. Rather, those have gone to rookie left-hander Sam Freeman.

"Sam has been throwing the ball well lately," Matheny said. "Marc has had a couple here lately that were tough situations. ... We're just at that spot, we've made no secret about it, we've got to go with the hot hand. People can read into it as much as they want to, but I keep talking to Marc and tell him we're ready to use him when situations are right. He just has to be ready to go when that happens."

Rzepczynski has pitched just three innings in seven September appearances. In two of those games, Rzepczynski was pulled after walking the only batter he faced. Perhaps the biggest indication of Rzepczynski's place on the depth chart came in Chicago last weekend.

Twice, Freeman was called upon to enter one-run games -- once with the team leading, the other with the Cards behind. Rzepczynski didn't make an appearance in the series.

Worth noting

• Manager Mike Matheny said the Cardinals will keep their five-man rotation as is, rather than using Thursday's off-day to switch spots around. If the Cardinals, who currently hold the second National League Wild Card spot, clinch a postseason berth before the final day of the season, they would then likely make some rotation alterations to set themselves up for the playoffs.

• Matt Holliday started again on Tuesday, even though the back tightness that plagued him in Chicago has not entirely gone away. Holliday went 1-for-5 with three strikeouts on Monday.

"He was chasing balls out of the zone," Matheny said. "That's what you saw more than anything else. There were a couple balls left up that he took some very, very healthy swings at. You really couldn't tell by the mechanics of the swing [that his back was hurting] as much as you could tell by the pitch selection. When he starts leaving the zone that much, you just anticipate that something might be bothering him."

• Houston native Woody Williams made a visit to the Cardinals' clubhouse on Tuesday. He spent time talking with former teammates Chris Carpenter and Lance Berkman, among others. Williams pitched in St. Louis for parts of four seasons. He closed his career in 2007 with the Astros.

• The Cardinals' nine-game winning streak over the Astros matches the longest in franchise history. St. Louis also won nine in a row over the Astros from July 9, 1971-April 29, 1972.