Owen Wilson is not happy about Kate Hudson and Lance Armstrong's romance.

The actor, who went officially off-again with Kate a few weeks ago, isn't taking his ex's rebound relationship too well, according to clubgoers who spotted him at club G in Philadelphia, OK reports.

"Owen looked pretty upset," an eyewitness tells OK!. "He was drinking and sulking until last call."

"Owen's been spending time on the phone with Luke," a Marley & Me set source tells OK!. "There are a lot of people making sure they're there for him."

"We all though it would be Owen breaking Kate's heart, but it turned out to be the other way around," a pal of the two tells OK!. "It's sad because deep down they love each other -- but they're too lethal a combination to last. And Kate has her son, Ryder, to think of."

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