He played at the Manchester Etihad stadium, and after belting out his classic Let Me Entertain You, Robbie took to the centre of the stage to deliver a message.
He said before playing the track: "This next song is dedicated to all the people that tragically lost their lives last week here in Manchester". "Sing it for them!"
He often made attempts to fill in the words but was too tearful to do so, as seen in a Twitter video captured by BBC Sports editor Stuart Rowson and Liverpool Echo deputy executive editor David Raven.More news: Trump 'evolving' on climate action, pressured by Europeans
After being greeted by his friends at Take That, the singer opened his set with his ballad Strong, but he put an emotional and Mancunian twist on the lyrics.
Struggling to sing the verses, the crowd helped him sing the song, as tears rolled down his face.More news: Environment minister calls US withdrawal from climate deal 'regrettable'
Opening his show, Williams told the crowd: "We are Manchester and we are not f**king scared" before later altering the lyrics in the chorus of Strong, as seen in the video below.
The concert was the first stop on Williams' Heavy Entertainment Show Tour.
He'll be back in Manchester with Take That for the Ariana Grande benefit concert next weekend.More news: London Bridge terrorists shouted 'this is for Allah' as they stabbed victims
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