HOUSTON -- Pry as we might, Houston manager Phil Garner wasn't going to spill the beans on what lineup changes he might have in store for Game 3 of the National League Division Series.

Bobby Cox was equally circumspect when asked about what tweaks might be coming from Atlanta's side when the two teams meet Saturday night at Minute Maid Park.

This much is certain: With the series tied at a game apiece, Garner and Cox will be pulling out all of the stops to try and nail down the all-important middle game of this best-of-five series.

"Could be," Garner said with a smile when asked if Saturday's lineup will differ from the starting eight he used in Atlanta.

When asked about the lineup a second time, Garner smiled again.

"I have it in mind," he said. "That's where it's going to stay for a little while. We'll see how the evening progresses, but I know what I'm going to do."

Cox also planned to wait until game day to reveal his lineup.

The mutual reticence is a manager's prerogative and in this case understandable considering the dynamite pitching matchup: 20-game winner Roy Oswalt for Houston against Jorge Sosa, the 27-year-old flame-thrower who blossomed into a 13-game winner for the Braves this season.

The Astros have been much more successful at home than on the road. Minute Maid Park is more hitter-friendly than Turner Field, so even though this is essentially another matchup of hard-throwing right-handers, look for both men to try and maximize every advantage.

Normally, that would include stacking the lineup with left-handed hitters, but with the Crawford Street boxes in left only 315 feet away, right-handed pull hitters or left-handed batters who have power to the opposite field are also options both men must weigh.

Garner, in particular, has some interesting decisions to make, such as whether to give Mike Lamb his first action of the NLDS.

Lamb is a dangerous left-handed hitter. Though he hit only .236 for the season, he was a force during the final six weeks, hitting .325 with five home runs and a dozen RBIs. Lamb also hit .333 against Atlanta this season (5-for-15) with three RBIs.

Houston fans also remember Lamb in the postseason last year, especially against St. Louis in the National League Championship Series where he hit .400 with a pair of home runs.

Lamb also is one of the few Astros who has faced Sosa. It's a very small sample -- which gives Garner even more to think about -- but in three plate appearances against Sosa, Lamb has an RBI single and two walks.

With the exception of Willy Taveras (2-for-2 with a homer), Craig Biggio (1-for-3) and Orlando Palmeiro (2-for-8), Lamb is the only other Astro with at least one hit against Sosa.

"My job is to be ready when [Garner] needs me," Lamb said. "Whether it's pinch-hitting or playing, I just need to be ready to go."

The hunch here is Lamb will be doing more than just cheering in Game 3.

Cox also has lineup-card decisions to mull over.

Does he stay with Game 2 hero Brian McCann at catcher or go back to Game 1 starter Johnny Estrada? First baseman Adam LaRoche is a dangerous left-handed hitter. He's also a career .231 hitter at Minute Maid Park. What about left field? Ryan Langerhans or Brian Jordan?

Cox will weigh his options and talk to the players Saturday before making his final decision.

"There's a number of ways we could go," Cox said. "Against a guy like Oswalt, you want every advantage you can get. We'll just have to wait and see."