Matt Smith wanted a "more brutal" 'Doctor Who' exit.
The actor - who played the eleventh Time Lord until his departure in the Christmas special in December - has revealed that many alternate versions were filmed for his final scenes and he wished they'd used a different "cut".
Speaking at the WonderCon Q&A, he said: "It's very interesting the Christmas episode and particularly the regeneration.
"We shot so many different versions of that - we shot much more brutal, emotional and troubling takes and stories in there. The actual take that is used is an interesting one for me.
"But to be honest, although it's still a great 'Doctor Who' episode, I think perhaps of what we shot and what was cut I would have chosen differently."
Although Matt has been replaced by Peter Capaldi - who will play the Doctor in the next series - he will reportedly appear in a cameo role in an upcoming episode.
A source previously claimed: "Doctor Who's sidekick Clara is struggling to accept that Capaldi is still her Doctor when she receives a phone call from Matt, which he made prior to his regeneration.
"It sounds confusing but he is ringing the future from the past and wants to assure Clara this new man is still Doctor Who."
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