Up periscope

It looked like a glorious start for Carlos Zambrano and Kosuke Fukudome — until the rains at Wrigley poured fourth again in the bottom of the third inning — sending the groundskeepers for the tarp at 2:41 p.m. for Opening Day’s second rain delay.

It’s coming down hard enough now to call into question whethet this thing might get finished or whether tomorrow’s open date might have to be used for an Opening Do-over.

“Perpetual window” is what Cubs manager Lou Piniella called the message from the weather people before the game. But was that 40-minute, 2 1/2-inning window the one? Anybody got the latest Doppler report?

If this renewal of the Cubs-Milwaukee division row get postponed, the innings that were played could be a frustrating what-might-have-been proposition for the Cubs.

While neither team has scored, Cubs ace Zambrano looks commanding today, striking out three of the 11 he’s faces, walking one and allowing only one ball out of the infield. And that wasn’t Tony Gwynn Jr.’s first-inning hit — it was Corey Hart’s fly to the wall that center fielder Felix Pie caught with a tougher-than-it-looked effort.

But the big highlight of the game so far came with one out in the Cubs’ second, when Japanese sensation Fukudome stepped to the plate at Wrigley for the first time since signing that $48 million contract — and drove the first U.S. pitch of his major league career over Gwynn’s head in center for a double.

He took third on Mark DeRosa’s fly to Gwynn, and rookie Geovany Soto drew a four-pitch walk to put runners at first and third with two out for the first scoring threat of the game.

Pie struck out swinging at a Ben Sheets pitch in the dirt to end the threat.

Stay tuned.