(My Sportsbook) - It was inevitable. The Chicago Cubs weren't about to go wire-to-wire with a comfortable lead in the NL Central. Luck, which is crucial to a squad's success in the long journey of a major league season, doesn't exactly run rampant on the north side of the Windy City.

Something bad was bound to happen and it came about when perennial power hitter Sammy Sosa (right big toe) hit the disabled list on May 10. Initially the injury to their star didn't stem their momentum, as they won five straight games. Of course, four of those victories came over the lowly Milwaukee Brewers at Miller Park.

Things turned dreary last Friday in the opener of a big four-game set against the St. Louis Cardinals. With the game knotted at 3-3 in the bottom of the fifth, St. Louis' J.D. Drew belted a two-run homer off Matt Clement to put his team ahead for good en route to a 7-4 victory.

Drew's home run seemed to shift the momentum of the Cubs' season and they have lost four of five overall. During the stretch, Chicago has managed only 11 runs for an average of 2.2 per contest.

The Cubs' woes continued on Wednesday against the floundering Pittsburgh Pirates at PNC Park. Chicago managed only seven hits and a pair of runs on its way to a 5-2 loss. The Cubs had trouble solving struggling hurler Jeff D'Amico, who improved to 6-0 with a 1.43 career ERA against the Northsiders.

Mark Grudzielanek was the lone Cub with multiple hits as he went 2-for-4 in the contest. Alex Gonzalez posted the Cubs' two RBI with a double in the eighth frame.

"They were more aggressive than we were," manager Dusty Baker said. "They took it to us. It seemed like they were a step ahead of us. We were a split-second slower all night."

Thanks to its struggling offense, the Cubs have seen their Central lead dwindle to 1 1/2 games over the trio of St. Louis, Houston and Cincinnati. Six of the Cubs' next nine games are against the Astros. Sosa's tentative target date to return is June 1.

Sosa is feeling better, but he was just able to put his shoe back on his foot on Wednesday. The perennial All-Star is excited about returning to the lineup.

"The hard times are behind me," Sosa told the Chicago Sun-Times. "I feel more life. I'm the kind of person that I like the action. I don't want to be sitting around. I miss being there because they need me. I don't care whatever everybody says, I'm a big piece of this team. I miss protecting my teammates."

WHO'S HOT

Young hurler Mark Prior has been very good in recent starts, not giving up more than one run in any of his past six outings. Prior, who owns the National League-low 2.02 ERA, gave up just six hits and a run over 7 1/3 innings in a no-decision against St. Louis. The 22-year-old struck out six and walked two in the contest.

WHO'S NOT

Eric Karros has seen limited time for the Cubs as of late for good reason, as he has just three hits in his last 17 at-bats. Karros has seen his batting average fall 49 points to .318.

COMING UP

The Cubs finish up their rain-shortened two-game series in Pittsburgh on Thursday night. Chicago remains on the road this weekend when it travels to Minute Maid Park to take on the Astros.