The first day of their Alfonso-free period didn't go smoothly for the Cubs, who failed to mount any offense Monday in a 2-1, 10-inning loss to the Astros.

Eric Munson's two-out RBI single off Michael Wuertz won it as the Cubs struck out 13 times to tie their season-worst effort and fell to 10-18 when facing a left-hander starter.

"You hold a team to two runs in 10 innings, you should win," exasperated manager Lou Piniella said.

The Cubs went 0-for-10 with runners in scoring position and struck out six straight times in the eighth and ninth innings. They remained one game behind first-place Milwaukee, which lost to Colorado 6-2 at Coors Field.

After Brad Lidge struck out Cliff Floyd with the go-ahead run on third in the 10th, Wuertz walked Ty Wigginton leading off the bottom of the inning. A sacrifice bunt advanced Wigginton to second and one out later he took third on a wild pitch. He scored the winning run on Munson's sharp single to right on a 3-2 slider.

Wuertz (2-3) blamed his leadoff walk for the outcome.

"It's that simple," he said. "Especially in an extra-inning game, a walk comes back to haunt you."

With Alfonso Soriano on the disabled list with a torn right quad, new leadoff hitter Ryan Theriot contributed a pair of doubles. But the rest of the offense looked lethargic against Astros left-hander Wandy Rodriguez and relievers Chad Qualls and Lidge (3-1), spoiling Rich Hill's strong outing.

The Cubs rotation of late has consisted of the Big Two and the three question marks, which isn't exactly the way to plan a stretch run for the postseason. Hill gave up one run on three hits over seven innings, striking out six and walking two.

"He gave us every opportunity to win," Piniella said.

In his previous two starts, Hill lasted a combined 9 2/3 innings, allowing six runs on 12 hits and six walks. Before the game, Piniella was asked if he would consider bringing up a starter from Triple-A Iowa, namely Sean Gallagher, to get a spot start and give the other five starters an extra day of rest.

"We've talked about that," Piniella replied.

Has it gone beyond the talking stage?

"I'm not saying that it won't," he said. "But we've talked about it. Nothing definitive."

Gallagher is 3-1 in five starts at Iowa with a 2.16 ERA, and is scheduled to start Wednesday against Las Vegas.

Hill's only mistake was Carlos Lee's opposite field, two-out home run on a 1-1 pitch in the fourth. Rodriguez, who matched Hill all night long, gave the run right back in the fifth, when Theriot doubled to right, advanced on a groundout and scored on Derrek Lee's RBI grounder to second.

Rodriguez lasted eight innings, yielding one run on four hits while striking out nine.

Asked if Rodriguez was that dominant, Piniella said "I really don't know. He threw the ball well, but I don't know if he was that dominant or not."

After Rodriguez struck out the side in the eighth, Qualls struck out the side in the ninth. The Cubs entered the game with a .248 average against left-handed pitching, ranked 13th in the league. They're now 1-7 in extra-inning games.

"We've held our own the last couple of weeks," general manager Jim Hendry said. "But we're not even close to everybody functioning on all cylinders offensively.

"I'm hoping when they get going, it stays that way. We have a lot of good players, but they're not on the top of their game together. You have to have four or five guys going real good at once to have a real good run.

"But I have to give our guys a lot of credit because they're grinding it out when there's a lot of pieces we wish would do even better."

psullivan@tribune.com