A California man who lost $500,000 during a Las Vegas trip over the Super Bowl weekend is suing the casino for his losses because he was blackout drunk.

Retiree Mark Johnston is suing the brand new Downtown Grand for loaning him the money and allowing him to play while he was inebriated.

Nevada law bars casinos from allowing visibly drunk patrons to gamble and from serving them comped drinks.

'I feel like they picked my pockets,' Johnston told MyNews3. 'I feel like they took a drunk guy...like a drunk guy walking down the street, and you reach in his pockets and grab all his money.'

According to Johnston's complaint, he drank at the airport and on the way to the hotel.

He and his friends at at a restaurant, then things get fuzzy for Johnston.

'After that, I don't remember anything,' he said.

But memory or no, Johnston appears to have had quite the time in Sin City.

So much so that he took out a loan with the hotel for $500,000. And promptly lost it all.

And therein lies their claim, said Johnston's attorney Sean Lyttle.

'You certainly arent't to issue half a million dollars in markers to someone who's intoxicated,' he said.