McFly drummer Judd and Lohan were romantically linked in 2005 when they both worked together on the movie Just My Luck.
Judd confessed in a new interview with The Mirror that he found their one-night-stand at a hotel "awesome" at the time, but insisted that he never had full sex with the actress.
"I was really nervous. Lindsay invited me back to her hotel. I left at eight o'clock next morning," he said.
"I didn't shag her but we spent the night and had a fumble. We did things teenagers do. We went far enough but not the full home run."
Lohan has always denied that she had a fling with Judd.
> Judd: 'Lohan turned me off celebrities'
> Harry Judd wins 'Strictly Come Dancing' 2011
Watch the Just My Luck trailer below: