Boilermakers and DJ Snorlax — that’s triple j‘s Matt Okine and Alex Dyson during business hours — have taken to Splendour In The Grass‘ Mix Up stage today for a not-so-secret ‘secret set’ featuring a performance of their one-line phenomenon, Pack ‘Er Up, Boys.

Footage has emerged online of Boilermakers and DJ Snorlax performing a super-energetic Splendour set after rapper Allday made a last minute exit from the festival due to a family emergency.

The Matt & Alex-shaped hole in the Splendour schedule was, of course, filled by some Matt & Alex shenanigans, complete with a remix of Pack ‘Er Up, Boys, which is yours to enjoy in the videos below.

Watch: Matt & Alex – Pack ‘Er Up Boiz (Splendour In The Grass 2015)

Pack er' up boiz @mattandalex pic.twitter.com/dycUMb7kVV

— Lilly McFrilly (@lillymcfrilly) July 26, 2015

Who knew they had it in them @mattandalex @alldaychubbyboy pic.twitter.com/gSXe1aIt9r

— Lilly McFrilly (@lillymcfrilly) July 26, 2015

Dynamic duo Boilermakers + DJ Snorlax (aka @mattandalex) raining down weather raps #SITG2015. Next stop: Ibiza? pic.twitter.com/HuouOUQuRl

— triple j (@triplej) July 26, 2015

Now that's a facepalm! @mattandalex taking it to the people during their set as Boilermakers + @DaRealDJSnorlax pic.twitter.com/vdRRW6eZzJ

— triple j (@triplej) July 26, 2015

Thanks to Emily for a special tribute to @alldaychubbyboy – spitting verses on Always Know The DJ #SITG2015 pic.twitter.com/WUYCDKcB2P

— Matt and Alex (@mattandalex) July 26, 2015

Not bad for our 3rd show. Boilermakers ft. DJ Snorlax making their presence felt #SITG2015 pic.twitter.com/UDMqcDklqr

— Matt and Alex (@mattandalex) July 26, 2015