On Tuesday, the 45-year-old BBC journalist said goodbye to the flagship programme ahead of his move to Channel 5, where he will replace Sian Williams as the lead anchor on 5 News.
WATCH: Dan Walker bid an emotional goodbye to BBC Breakfast
Following his departure, former Good Morning Britain host Piers took to Twitter to write: "End of an error. Congrats mate. @mrdanwalker." To which, Dan replied: "Thanks… I think."
Over the years, Piers and Dan have repeatedly fired thinly-veiled shots at each other as their competing shows clashed in a continuous ratings war.
Last year, Dan touched upon their rivalry following Piers' unceremonious exit from GMB. The outspoken broadcaster had quit the ITV breakfast show over comments he made after Meghan Markle and Prince Harry's divisive Oprah Winfrey interview.
Dan hosted his final show on BBC Breakfast on Tuesday
During a chat with The Sunday Times, the BBC journalist claimed that there's "a decent bloke fighting to get out" of Piers. He said: "Piers [Morgan] and I have had a friendly rivalry, but it has been good for BBC Breakfast and GMB.
"He likes to throw a few insults around, but underneath all the froth I think there is a decent bloke fighting to get out."
Of their different approach to interviewing, Dan added: "They are very different programmes and I've always said GMB do a good job. Our styles are very different, but the idea that you've not done a good job unless you demand resignations and rant at the interviewee is laughable.
"I don't want you to know my opinion. I have no problem being seen as the more measured presenter."
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