Mark Hamill told Arnold Schwarzenegger to lose his accent and changed his name if he wanted to be a Hollywood success.
The 'Star Wars' icon was approached by the 71-year-old actor for some advice when he was embarking on a movie career but he admitted the 'Terminator' star was right to ignore his suggestions.
He tweeted: "Arnold Schwarzenegger asked me for advice when he was just starting out. I told him to lose his accent for a wider range of roles & to change his last name since no one could pronounce it.
"He did the opposite & became one of the biggest stars EVER #TrueStory.(sic)"
However, the 'Predator' actor has no hard feelings towards Mark, 66, insisting his advice was "absolutely correct" but he chose to ignore it because he doesn't like to follow the rules.
He tweeted in reply: "Your advice was absolutely correct under any normal circumstances, and those were the rules back then. I just happen to be a rule-breaker."
Meanwhile, Mark recently called for US President Donald Trump's star on the Hollywood Walk of Fame to be replaced by one honouring his late 'Star Wars' co-star, Carrie Fisher.
There have been numerous calls for the US Leader's accolade to be removed by the Los Angeles City Council and the Hollywood Chamber of Commerce following repeated vandalism by protesters.
And Mark tweeted: "How about replacing it with someone who really earned it? Like @carriefisher (sic)"
The majority of his fans are in agreement, with one user airing their frustrations at the fact that Carrie - who died in 2016 at the age of 60 - didn't already have her own star.