Gwyneth Paltrow insists Utah ski collision wasn't her fault

'My brain was trying to make sense of what was happening,' celebrity says of incident

US actress Gwyneth Paltrow gives evidence during the trial in Park City, Utah. AFP

Gwyneth Paltrow insisted on Friday that a collision at an upscale Utah ski resort in 2016 was not her fault, claiming the man suing her smashed into her from behind.

“I was confused at first and I didn't know exactly what was happening,” she said in the witness box, describing the incident.

“It's a very strange thing to happen on a ski slope. I froze and I would say I got very upset a couple of seconds later.”

Paltrow and Terry Sanderson, the retired optometrist who is suing her, are both expected to be grilled on the crash while their lawyers attempt to convince the eight-member jury which skier was positioned downhill and who had the right of way.

Throughout Paltrow’s heavily anticipated evidence, the Oscar-winning founder and chief executive of Goop has calmly and repeatedly said that Mr Sanderson, who sat a couple of metres away in court, had crashed into her.

“I did not believe his testimony,” Paltrow said.

“Mr Sanderson hit me and that is categorically the truth.”

The crash broke four of Mr Sanderson's ribs and left him concussed.

Mr Sanderson and his four-member legal team dispersed themselves throughout the courtroom to re-enact the crash for the jury, whose members perked up after days of yawning through jargon-dense medical evidence.

Paltrow's lawyers objected to her participation in such a re-enactment.

While Mr Sanderson’s lawyers have focused on their client’s deteriorating health, Paltrow’s legal team has intrigued the jury with recurring questions about the mysterious missing GoPro footage that may contain the collision. No video footage has since been located or entered as evidence.

The trial thus far has shone a spotlight on Park City, Utah — the posh ski town known for rolling out a red carpet for celebrities each January during the Sundance Film Festival — and skiers-only Deer Valley Resort, where Paltrow and Mr Sanderson collided.

The resort is among the most upscale in North America, known for sunny slopes, apres-ski champagne yurts and luxury lodges.

The proceedings have delved deep into the 76-year-old Mr Sanderson's medical history and personality changes, with lawyers questioning whether his deteriorating health and estranged relationships stemmed from the collision or the natural process of ageing.

“I don't believe he saw what he thinks he saw. He said he was 40 feet [12 metres] away and colour blind. I don't know how he can be positive with what he saw, especially with how much he changed his story,” Paltrow said.

“If you have two people in ski gear with helmets on and you're 40 feet away, I don't know how you can discern who is who.”

After a judge threw out Mr Sanderson's earlier $3.1 million lawsuit, Mr Sanderson then claimed damages of “more than $300,000".

Paltrow has countersued for a symbolic $1 and legal fees. In 2017, Taylor Swift similarly countersued a radio host for the same symbolic amount of $1.

Gwyneth Paltrow in Park City courtroom in Utah for the start of a trial over a 2016 skiing crash. AP

Terry Sanderson, 76, a retired optometrist is suing the actress accusing her of colliding with him at Deer Valley Resort in 2016. AFP

Ms Paltrow and her lawyer Steve Owens. AP

Mr Sanderson claims that the collision left him with brain damage and four broken ribs. EPA

Mr Sanderson also claims Ms Paltrow was cruising down the slopes so recklessly that they collided, leaving him on the ground. EPA

The actress-turned-influencer covers her face as she exits the courtroom. EPA

Ms Paltrow hides her face as she leaves the courtroom. AFP

The actress outside the courtroom after the first day of testimony. AP

Agencies contributed to this report