CHICAGO (AP) âÄî Ryan Dempster stepped out in front of the teamâÄôs headquarters at the beginning of spring training nearly seven months ago and made a bold statement: He said he thought the Chicago Cubs would win the World Series. DempsterâÄôs optimism remains intact, despite a recent funk that has seen the first-place Cubs drop five straight games for the first time this season. And not only are the Cubs trying to weather the losing skid, they learned Thursday that ace Carlos Zambrano has rotator cuff tendinitis, a condition that required an injection of anti-inflammatory medication. Zambrano, who will miss his turn Sunday in Cincinnati, hopes to begin throwing in St. Louis when the Cubs go there next Wednesday. And if all goes well, he could rejoin the rotation for a series in Houston and pitch against the Astros. âÄúItâÄôs a relief knowing Z doesnâÄôt have anything more significant than what we thought. And hopefully heâÄôll pitch in Houston, which means he will only miss one turn,âÄù general manager Jim Hendry said Thursday. So, in the 100th anniversary year of their last World Series win, the Cubs are sorting out some major issues. They have 22 games remaining and just six are at Wrigley Field, where they are 51-24. âÄúObviously you lose five in a row and donâÄôt play as well as you are capable, itâÄôs frustrating for everybody,âÄù said Dempster, who has 15 wins after being converted from a closer. âÄúThere are better times ahead. I promise that.âÄù But will those days ahead include Zambrano? Big Z left his start Tuesday night after five innings, telling pitching coach Larry Rothschild he didnâÄôt feel well and wanted to be taken out. He had been slated to pitch last Sunday but got two days extra rest for what was described as a tired arm. His right arm was more than just weary. Zambrano, on the disabled list in June with a sore shoulder, was examined by team orthopedist Dr. Stephen Gryzlo and then had an MRI on Thursday that confirmed the original diagnosis. âÄúDr. Gryzlo has been right-on with all his evaluations this year, and he felt this was not going to be a significant problem,âÄù Hendry said. âÄúIt was not like the situation where he had to be put on the DL after Tampa. And Carlos never felt it was going to be that serious either.âÄù