After helping the Cubs climb back into the NL Central race by going 9-3 with a 1.98 ERA through June and July, Carlos Zambrano looks like a different pitcher in August.

Through three starts, Zambrano has had one cut short by cramps; let up seven runs in his next outing; and followed that up by letting up six runs on 13 hits without striking a single batter out. He's 0-2 with an ERA north of seven this month.

Is there something wrong with Zambrano? There was speculation about the health of his shoulder in the spring after he stumbled out of the gate. That was put to rest for a while after his hot June and July. But his recent struggles are causing more speculation about the health of his pitching arm. Cubs pitching coach Larry Rothschild insists he's fine, which raises red flags that something really is wrong.

If he is injured, it couldn't come at a worse time for either the Cubs or Z. The Cubs, after catching the Milwaukee Brewers in the NL Central standings, have been awful. They've lost 10 of their last 13. While the Brewers haven't been much better the past two weeks, the St. Louis Cardinals are rapidly closing ground on the Cubs and Brewers. If the Cubs have any hopes of taking the division crown, they need Big Z.

Any injury could also be costly for Zambrano personally. For a while there, it looked like the impending sale of the Cubs and the Tribune Co.'s rescinding of their $72 million, five year offer might end up helping Zambrano. As the premier free agent pitcher on the market this winter, he might be looking at a nine-figure contract. But his market value would clearly diminish if he limped to the finish line or even landed himself on the DL. Is he simply fatigued? Is he just in a bit of a slump? Or maybe something really is wrong with Zambrano's pitching arm.