It's a good week for live music in Sydney. 

Bruce Springsteen performed his second show in town last night to another packed out crowd and apparently fellow US rock icons Guns N' Roses were in attendance. 

The Gunners are set to kick off the first of two shows in Sydney tonight, but a few of the band members look to have taken Thursday night off to be a part of the audience at Qudos Bank Arena, rather then the main event, as they will be in front of 60,000-plus tonight at ANZ Stadium.

Slash and Duff McKagan both took to Twitter following Springsteen's show to praise the set. 

So, if you spotted a guy with curly black hair and a top hat on at the show, you know who you saw now.

The only question now is will the Boss return the favour for Guns N' Roses at ANZ Stadium tonight? Time will tell.

Check out a review of the Gunners' set in Brisbane earlier this week here.

Guns N'Roses + Wolfmother
Adelaide Oval, North Adelaide
Guns N'Roses + Wolfmother
Domain Stadium (formerly Patersons Stadium), Subiaco