CHICAGO -- Carlos Zambrano threw on the side Thursday and reported no problems with his back. The right-hander is expected to be activated from the disabled list Saturday to start against the Marlins.

Zambrano (6-4, 4.34 ERA) has been sidelined since July 1 because of lower back soreness.

Randy Wells (1-3, 6.80 ERA) will start Sunday and Rodrigo Lopez (1-2, 4.02 ERA) will go Monday when the Cubs face the Phillies. The Cubs needed to chose between Lopez and Ramon Ortiz for the fifth spot in the rotation. Ortiz, 38, was expected to go to the bullpen.

Andrew Cashner, who has been on the disabled list since April 6 with a strained right rotator cuff, was back in Mesa, Ariz., to continue his rehab. He will continue to build arm strength by throwing long toss before working toward throwing off a mound in a couple weeks.

Castro's first All-Star experience memorable

CHICAGO -- Starlin Castro watched the Home Run Derby with his two brothers on the field in Phoenix on Monday. He also got to meet Cal Ripken Jr. Then in Tuesday's All-Star Game, Castro stole two bases, made an error, and returned with a souvenir All-Star jersey signed by his National League teammates.

Cubs manager Mike Quade, on the other hand, ended his All-Star experience with a 40-minute delay while he and his belongings were searched at Sky Harbor Airport in Phoenix.

Castro was the Cubs' lone player representative, while Quade was a coach on the NL staff at Chase Field.

"I enjoyed it a lot with my family," said Castro, who subbed for the Rockies' Troy Tulowitzki at shortstop. "It was pretty fun."

Castro brought his parents and two brothers, who were on the field to watch the Home Run Derby. He met Ripken, who apparently has been keeping an eye on the Cubs' 21-year-old shortstop.

"He told me he's watched me play," Castro said Thursday. "He said, 'Keep going, you're a good player. Play hard.'"

It was nice to be able to hang out with the All-Stars.

"I learned a lot of things," Castro said. "I hung out with a lot of superstar players. I'm a superstar now, too."

Is that hard to believe?

"Yeah, really hard," he said.

Quade's belongings apparently set off an alarm as he went through security at the airport on his return flight to Chicago. He and Castro started their journey on a tough note when they couldn't get out of Pittsburgh on Sunday night and had to be re-routed through Memphis on Monday.

On Tuesday, Quade got the full pat-down, and Transportation Security Administration (TSA) personnel screened his belongings about four times.

"I don't know what they were looking for," Quade said.

TSA did find a gold necklace in his computer bag that may have set off the alarm. The delay was exasperating and spoiled what had been a terrific time.

"[The All-Star Game itself] was a great experience -- and we won -- and that matters," Quade said.

Quade on same page with Dempster

CHICAGO -- Cubs manager Mike Quade talked to Ryan Dempster to explain his rationale for taking the right-hander out of last Saturday's game after 87 pitches over five innings, a decision Dempster didn't agree with at the time.

"Everything's fantastic," Quade said Thursday.

Quade met Dempster at the dugout steps in Pittsburgh after the fifth to tell the pitcher he was done for the day. Dempster was clearly upset, and argued with his manager.

"It's like anything else, if you argue with a player or a coach or people at home," Quade said. "It's a different interpretation of what's going on, and often that's not considered at that moment."

The Cubs manager also addressed his players before Thursday's workout at Wrigley Field, as the team prepared to open the second half against the Marlins. The message?

"There's a lot of things out of our control, so let's make sure we take care of the things we can control, whether it's executing fundamentals or whatever the case may be," Quade said.

Cubs sign pair of Draft picks

CHICAGO -- The Cubs have signed outfielder Zeke DeVoss, their third-round selection from the 2011 First-Year Player Draft, and their sixth-round selection, catcher Neftali Rosario.

DeVoss, who turns 21 on Sunday, recently completed his sophomore year at Miami. This season, he batted .340 with 13 doubles, three triples, two homers, 27 RBIs, 59 runs scored, a .491 on-base percentage and 32 stolen bases in 42 attempts. He led the Hurricanes in most offensive categories.

A switch-hitter, DeVoss was originally drafted by the Red Sox in the 38th round of the 2009 Draft, but he did not sign.

Rosario, a catcher who played at the Puerto Rico Baseball Academy High School, also has agreed to terms. The Cubs now have signed eight of their top 22 picks.