By RICK GANO
AP Sports Writer
CHICAGO -- Ryan Dempster stepped out in front of the team's 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.
Dempster's 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. 10. And if all goes well, he could rejoin the rotation for a series in Houston and pitch against the Astros.
"It's a relief knowing Z doesn't have anything more significant than what we thought. And hopefully he'll pitch in Houston, which means he will only miss one turn," 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.
"Obviously you lose five in a row and don't play as well as you are capable, it's frustrating for everybody," said Dempster, who has 15 wins after being converted from a closer. "There are better times ahead. I promise that."
But will those days ahead include Zambrano?
Big Z left his start Tuesday night after five innings, telling pitching coach Larry Rothschild he didn't 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.
"Dr. Gryzlo has been right-on with all his evaluations this year, and he felt this was not going to be a significant problem," Hendry said. "It 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."
Chicago also is taking a cautious approach with hard-throwing Rich Harden -- who will go 12 days between starts because he has some discomfort in his arm. Sean Marshall will start for Zambrano on Sunday.
"There's no good time when people are out," Hendry said. "We have a lot of confidence in Marshall, Dempster's had a great year, Ted Lilly's as tough as they come and (Jason) Marquis has been throwing the ball real well."
Sore arms, bad luck and strange occurrences are part of the Cubs' lore, especially since their 2003 collapse in the NLCS, when they were five outs from their first World Series appearance since 1945. In the ensuing seasons, repeated arm problems for Kerry Wood and Mark Prior sidetracked the Cubs and eventually led to the departures of both manager Dusty Baker and chief executive officer Andy MacPhail. Wood has since returned as a top closer.
Manager Lou Piniella established a "Cubbie Swagger" as he called it last season, leading the team to the NL Central title before the Diamondbacks swept the Cubs out of the playoffs.
This season, Cubs have been solid in most phases throughout and at one point last month had the best record in the majors -- overcoming two disabled list stints for star leadoff hitter Alfonso Soriano and one in June for Zambrano, when his shoulder was sore.
Zambrano is 13-5, but just 1-1 in his last six starts, when he's made it past the fifth inning only twice.
"Can we win without him?" second baseman Mark DeRosa said Thursday, repeating a question. "Of course we can. You don't want to have to do it."
Chicago began the day with a 4 1/2-game lead over Milwaukee in the division, but the stretch ahead includes a trying final week, when the Cubs play four at the New York Mets and three at Milwaukee. Chicago is 34-31 on the road.
"Do I feel we are going to be in postseason? Yeah, you're darn right I do," Piniella said. "But at the same time, we got to go do it on the field."
The Cubs' trip that starts at Cincinnati on Friday also takes them to St. Louis and Houston.
"We're in a tough little stretch now, where things aren't going our way and we've had some injuries," Piniella said. "No team is immune from a little struggle, and we're struggling some now. But look, all we need is to win a baseball game and get back on track."