CHICAGO -- Cubs third baseman Aramis Ramirez remained sidelined Tuesday with a bruised left thumb, and there's no timetable for his return.

Ramirez did not start Sunday and is hitless in his past four games. He's batting .160 overall.

"I'm sure the discomfort in his hand hasn't helped," Cubs manager Lou Piniella said.

There's been no talk about putting Ramirez on the disabled list.

"We haven't discussed that," Piniella said. "If he's going to be out for an extended period of time, that might change."

Jeff Baker started at third base on Tuesday against the Dodgers and lefty Clayton Kershaw.

Big Z will return to rotation to face Bucs

CHICAGO -- Carlos Zambrano appears ready to return to the Cubs' rotation next week against Pittsburgh, while Tom Gorzelanny passed all the tests in a side session Monday and will start Wednesday against Los Angeles.

Zambrano, who has been in the bullpen since April 22, threw 73 pitches in a simulated game Monday at Wrigley Field and will return to the rotation for one of the Cubs' games against the Pirates from May 31-June 2. The team will be one pitcher short Tuesday and Wednesday, but Zambrano will be available in the bullpen Thursday against the Dodgers if need be, Cubs manager Lou Piniella said.

The Cubs are not going to have a six-man rotation, but who will be bumped has yet to be determined.

"We don't have to concern ourselves with it until next week, and we have some days off coming up," Piniella said. "It'll be a fairly smooth transition."

Zambrano made four starts before he switched to the bullpen to help bridge the gap to closer Carlos Marmol. In 11 relief appearances, Zambrano is 0-1 with a 4.76 ERA, giving up six runs on 16 hits over 11 1/3 innings. Three of those runs came in a relief outing on May 14 against the Pirates that prompted Zambrano to ask to return to starting.

"We'll use him short with the idea that on this coming road trip, we'll insert him into the rotation," Piniella said.

Zambrano's outing Monday went better than expected. The Cubs projected him throwing 65-70 pitches and he easily threw 73, facing Tyler Colvin and Jeff Baker.

"He's ready to go," Piniella said of Zambrano, who was 1-2 with a 7.45 ERA in four starts. "His velocity was good. He worked on his split finger, worked on his cutter. He had a nice workout, a real nice workout."

Gorzelanny may be the odd man out of the rotation. Carlos Silva is 6-0. Ryan Dempster is 2-4 with a 3.73 ERA heading into Tuesday's game, but he has gone six or more innings in each of his starts. Ted Lilly and Randy Wells both are better suited for the rotation.

Wednesday will be Gorzelanny's first start since he was struck on the ring finger of his left hand May 20 in Philadelphia. He had returned to Chicago after that game to be examined and to be with his wife Lindsey for the birth of their first child on Friday.

"It was good timing to be able to go home," Gorzelanny said Tuesday. "It was nice to be able to help my wife out and get her back home and give her a hand."

Howry hopes to help out in bullpen

CHICAGO -- Bob Howry is hoping he can put together a solid second half with the Cubs beginning now.

The right-hander, whom the Cubs picked up after he was released by Arizona, has done better after the All-Star break, posting a career 3.28 ERA. Before the break, he has a 4.28 ERA.

"I've never tried to think of myself that way -- I always thought I could do it from the beginning," Howry said Tuesday, his first day back at Wrigley Field. "But statistically, it's shown that. If that's the case, it looks like it's ready to turn."

Howry was one of three pitchers who worked out Monday at Wrigley on the team's off-day.

"We'll use him in the middle," Cubs manager Lou Piniella said. "It gives us some experience. He was working with [pitching coach] Larry [Rothschild] on some things [Monday], working on his split finger. We want him to use that more."

Howry's first two seasons in Chicago in 2006-07 were solid as he appeared in 84 and 78 games, respectively. But he struggled in his third season in '08, going 0-7 with a 5.35 ERA in 72 games.

This year, he had given up 17 earned runs on 18 hits and six walks over 14 1/3 innings for a 10.67 ERA in 14 games with the D-backs.

Cubs general manager Jim Hendry talked to Howry before he signed.

"[Hendry] asked me if I thought I had anything left and if I could go out and pitch," Howry said. "I said, 'Yes.' If I didn't, I'd still be sitting at home. If I didn't believe I could come back and be successful, I wouldn't be here."

Cubs to move radio channels for Blackhawks

CHICAGO -- You'll have to tweak your radio dial to listen to Cubs games now that the Chicago Blackhawks are in the Stanley Cup Finals.

WGN Radio announced Tuesday it will air all of the Blackhawks' playoff games, and some of them conflict with Cubs' broadcasts. The Cubs' games will be heard on WIND 560 AM on June 2, June 4 and possibly June 9, if Game 6 of the Stanley Cup Finals is necessary.

On June 2, the Blackhawks will play the Philadelphia Flyers in Game 3 of the best-of-seven series, while the Cubs will be at Pittsburgh.

On June 4, the Blackhawks and Flyers will meet in Game 4 on WGN Radio 720 with the Cubs' game against the Houston Astros on WIND 560 AM.

If Game 6 is necessary, the Cubs' game against the Milwaukee Brewers also will air on 560 AM.