Sean Penn

The ‘Milk’ actor – who had a stormy four-year marriage to the singer from 1985 to 1989 – attended her show at the Staples Center and onlookers revealed he was quite impressed with her raunchy stage performance.

A source told RadarOnline: “He was practically panting. Every time she thrusted or bent over, he was like ‘Oh, man! I can’t take this! She is too hot!’

Despite their volatile marriage, there is no bad blood between the pair and Madonna reportedly even teased Sean from the stage.

The witness said: “At one point she stared Sean dead in the face, smiled, unzipped her pants, and mooned the crowd, but it was really like she was mooning Sean! He laughed and clutched his chest like he was going to pass out. She was wearing a black lacey thong, and her butt looked perfect! So smooth and tight….like a 20 year old’s!”

Meanwhile, Sean went backstage to congratulate Madonna after her performance and witnesses said he was “like a teenage boy meeting his idol. It was amusing, and kind of cute”.