Excuse us for thinking it's circa 1985!
The Oscar winner, 52, was right at the front at Madonna's gig at Staples Center in Los Angeles and could not keep his eyes off of her.
"He was practically panting," an eyewitness told RadarOnline. "Every time she thrusted or bent over, he was like, 'Oh, man! I can't take this! She is too hot!'"
Rita Wilson apparently joked to Sean, "Just like old times" to which he responded, "You're not kidding!"
The Material Girl's on-stage antics were not as explicit as usual because her 12-year-old son Rocco was one of her backup dancers and six-year-old son David was helping out in the DJ booth – but she obviously still likes to shock and got Into The Groove.
"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!" the bystander said.
"He laughed and clutched his chest like he was going to pass out. She was wearing a black lacy thong, and her butt looked perfect! So smooth and tight… like a 20-year-old's!"
Sean's night of reminiscing didn't end when the curtain went down because the Milk star went backstage to gush over Madonna some more.
"Sean was like a teenage boy meeting his idol," the insider said. "It was amusing, and kind of cute."
And Sean even went back to Madonna's trailer later in the night to catch up some more and Cherish the time with her.
Madonna and Sean tied the knot back in 1985 but had quite the rocky marriage and divorced four years later.
Do you think Madonna and Sean Penn should get back together?
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