A winning Lotto Max ticket, bought one year ago Saturday, has yet to be claimed. ((CBC))

Saturday is the last day for a mystery lottery ticket winner to come forward and claim a $1 million prize.

The winning Lotto Max ticket was bought on Aug. 6, 2010, somewhere in Dartmouth, N.S. Time is running out for the winner to collect his or her winnings — after a year, the money goes back into the pot.

"Well, my records go back as far as three years," said Sarah McBeath, spokeswoman for Atlantic Lotto. "And in the last three years, no one has ever let a major prize of $1 million or more expire."

Barry Diamond said he always checks his lottery tickets, so he's sure he's not the mystery Lotto Max winner.

"I can't believe even buying a ticket if you don't check it," he said Friday.

But when he heard that someone who won $1 million hasn't come forward yet, even he wants to be certain.

"Maybe I should check it again, should I?" Diamond asked.

Betty Giberson also doubts herself.

"I'm going to go look in all my old purses," she said. "Right tonight."

This ticket expires at 10 p.m. on Saturday, so the winner should call Lotto Max as soon as possible.