The singer suffered several injuries including a damaged ear drum and broken jaw after being attacked in a bar outside Manhattan, which led to the singer cancelling some upcoming gigs.
His manager Jim Dawkins had confirmed in a statement that Grennan's upcoming Washington DC show would be called off, following this "unprovoked attack".
Last weekend, Grennan took to Twitter, posting a message that he was in good spirits, despite being on medication.
Check it out below.
He told his US fans that the states is his "main priority", and that he did not want to let fans down.
"I thought I'd come on here and let you know that I'm all good and that the support that I have been seeing is unbelievable and very overwhelming and I can't believe it, so thank you so much", the Little Bit Of Love singer said.
"This 24 hours has been crazy. It's been a bit of a madness, to be honest with you. But I thought I'd come on here and let you know what actually went on. It was just wrong place, wrong time. And I was punched, knocked out and I woke up and I was like, 'Woah, what went on?'.
"I have got a ruptured eardrum. Luckily enough, my jaw is fine. I have got a bit of concussion but I am on meds at the moment so that is kind of taking the pain away. I filed the police report and the NYPD were great, they were brilliant. Wrong place, wrong time. But just a crazy 24 hours".
Tom Grennan once revealed during an interview in 2018, that he decided to pursue a music career after recovering from another violent attack in his youth.
He also grew up with his Irish family in Bedford. The singer's roots are in county Offaly.
