In a statement read out in court, Sarah White, a BA cabin crew member, said she had served the golfer, who was travelling first class, with a glass of champagne before take-off, followed by a vodka and cranberry juice.

She said she had also noticed him drinking champagne from another passenger’s glass.

Ms White said at one point she had noticed Mr Olesen struggling to get out of the aircraft lavatory by pushing at a pull door, but when she tried to help him he pushed her and said: “It’s all about you isn’t it, just go away.”

She said: “During the flight, Mr Olesen assaulted me and failed to listen to my instructions. Through my 27 years of service, I have never come across such bad behaviour on board a flight.”

Graham Gee, a crew member, then tried to intervene to get Olesen back to his seat, but he grabbed his hand and began to kiss it, the jury was told.

A woman, who cannot be identified, also gave a statement in which she claimed Olesen had grabbed her hand and started to kiss it.

She said: “He would not let go and then nuzzled his face into the nape of my neck. I felt he clearly didn’t know what he was doing.

“He had his right hand around my back. With his left hand, he then grabbed my breast and moved his hand over my right breast. I felt shocked, he had overstepped the mark.”

The court heard that Mr Poulter – also a member of Europe’s Ryder Cup team – felt his fellow golfer was “in a good mood” and “very jovial” when he boarded the flight.

He said he had taken some sleeping tablets but had not given any to Mr Olesen.

“I was unaware of what happened. I assisted with bringing him back to his seat. He looked a little bit worse for wear and I just assumed he had too much to drink,” he explained.