Crunch time for David Blaine

Thursday, April 24th 2008, 4:00 AM

David Blaine has a funny idea about fiber supplements.

The illusionist was dining with pals including pro poker champion Phil Ivey the other night at Tao in midtown, when he was given a remarkable challenge.

"David was doing a bunch of tricks, but Phil wanted to see something spectacular," a witness tells us. "He offered David $10,000 to eat a glass from the table."

So Blaine smashed a "rather large" sake glass and swallowed it piece by piece.

But it was just an illusion, right?

"This did happen and was completely real," his rep assured us.

Better stand aside if he burps!

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