Tiger Woods Partying with Smokin' Hot Blonde Paulina Gretzky!

Ryder? He hardly knows her!

Here's Tiger Woods hanging with Paulina Gretzky at a Ryder Cup celebration party -- which begs the question ... where's Dustin Johnson???

Kidding ... maybe ... kinda.

Of course, Tiger was the Vice Captain for Team USA -- which put the smack down on Team Europe over the weekend. Dustin played for the American team.

During the victory party, Paulina and Tiger got together for a pic.

Paulina looked insanely hot as usual. Tiger looked ... single.

Don't worry, TW -- you'll find the right woman one of these days.