Douglas Sumiyoshi, 43, had bought his winning Powerball ticket at Cable Car Wine & Spirit Grocer at 841 Clement St. in San Francisco for the July 13 draw, according to lottery officials.
But when the numbers were read, Sumiyoshi was busy with visiting friends and didn't get around to checking them for nearly two weeks.
"The ticket just sat on a shelf," Sumiyoshi told lottery officials.
When he stopped by Cable Car again this week he was on the verge of throwing the ticket away but decided to check the numbers first. When he saw the numbers matched, and learned the ticket was worth $2.6 million, he thought he had to be mistaken.
"I wasn't sure it was right, so I went to the clerk and showed her," he said. "She said, 'Yes, yes! You won! Come with me, look!"
The clerk showed him a sign on the front of the store, which he had failed to spot previously, that said the winning ticket had been purchased there.
"That's when I knew it was real!" Sumiyoshi said.
His winning numbers were 8,37, 2, 35 and 22. He missed only the Powerball number of 6.
Powerball is a multi-state game involving California and 44 other jurisdictions.