Matt Damon was originally tapped to play the part of James T. Kirk’s father George.
At one point in time, Damon was rumored to have been the pick for playing James T. Kirk, but it turns out that the rumor was only partly correct, as Damon was approached by J.J. Abrams to play the role of George Kirk.
When asked if he had called up Damon regarding the role of James T. Kirk, Abrams said “I did, but not for the role of James Kirk. I went to Damon for the role of Kirk’s father, and he declined in the most gracious and understandable and logical of reasons.”
Instead the part went to Chris Hemsworth. “We lucked out with Chris Hemsworth, and he did a great job,” said Abrams. “Maybe it would have been distracting to have someone as massively famous as Matt Damon in that role. The decision was made very early on to have actors who were not necessarily the most famous but the most right for the role.”