Taking to social media, the actor, who plays Jamie Fraser in the beloved historical drama, wanted to pay tribute to the Claire Fraser actress on her casting anniversary!
WATCH: Sam Heughan and Caitriona Balfe's real-life friendship
Sam retweeted a post shared by the drama's official Twitter account which read: "It's been nine years since we found our Claire and we've cherished her every day since. Happy casting anniversary to the incomparable @caitrionambalfe! #Outlander."
The Scottish actor then added his own words above, tweeting: "It's today!!!!! Congrats Balfe the OG Sassenach x." Caitriona herself then acknowledged the special day. The Belfast actor said on Twitter: "Wow. I can't believe it has been nine years.
Sam Heughan and Caitriona Balfe have formed a close friendship through their time on the show
"I guess time flies when you're having fun, getting to live your dream and spend it with an amazing group of people. As always thank you @Writer_DG for creating this incomparable character who has given me so much…"
Caitriona then went on to thank a number of other people involved in the Starz show including the production company, before adding: "What an amazing ride it has and continues to be …and of course … thanks to all the amazing fans who keep wanting more, so we get to continue this joyride!!!"
The stars play on-screen couple Jamie and Claire Fraser
Fans were equally thrilled by Caitriona's important milestone. One person wrote in response: "Claire on the pages was fantastic; Claire on the screen is an icon. Thank you for your hard work & dedication to this character & looking forward to seeing what Season 7 brings her."
Another said: "Oh my goodness Caitríona!! What a HUGE pleasure it's been to watch you bring #ClaireFraser to life on the screen!! You have been beyond brilliant. So many Congratulations; there just couldn't have been anyone else to play her like you do."
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