Kelly last night won the 'Serial Drama Performance' prize for her portrayal of Weatherfield's Becky McDonald, but was not present at the O2 arena to collect the gong as she was on stage in She Stoops To Conquer at the National Theatre. Fans saw her former co-stars Paula Lane (Kylie Platt) and Ryan Thomas (Jason Grimshaw) collect the gong on her behalf.
The 32-year-old - who was seen bowing out from the cobbles on Monday - later appeared on ITV2 show National Television Awards: The Party to discuss her triumph.
Kelly told viewers: "I'm literally half-way through the show at the National Theatre and I am so devastated that I didn't get to speak to everybody at The O2! The audience have been laughing their heads off all evening, so the first half ran for a lot longer than we thought.
"Thank you for this opportunity for me to say personally to the nation, to the Great British public, to the Coronation Street viewers, thank you so much for this award.
"Honestly, I have had such a wonderful week, such a wonderful five years - and this is the icing on the cake. The support for Becky has been just overwhelming from the beginning. Thank you for loving her as much as I have, and I'll never, ever forget it!"
Writing on Twitter later, she added: "Can't believe it, an NTA!!! And I'm not there! THANK YOU. Just recorded a personal message from the theatre for ITV2! Overwhelmed with joy!"
Becky's exit from Weatherfield pulled in a huge 11.5m viewers earlier this week.
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Watch a preview of tonight's Coronation Street episode in the video below: