For reasons that have yet to be disclosed, Adler was unable to accompany the band on the cruise, which departed from Galveston, Texas on January 22 and will dock in Cozumel, Mexico on January 27.
You can check out some fan-filmed footage of a rain-soaked Lamb of God performance on the cruise – with Demmel and his trademark Jackson V guitar clearly visible on the left hand side – above.
It's not the first time in recent months that a veteran metal outfit in need has called on Demmel.
Just two months ago, in November, Overkill recruited him for their first live gig in almost two years when the band's usual guitarist, Dave Linsk, had a scheduling conflict.
In his own right, Demmel is currently gearing up for the release of Let the World Burn, Vio-lence's first new music in 29 years.
The EP's lead single, Flesh From Bone, is a feast of classic thrash metal lead guitar heroics, complete with a blistering solo from Demmel that's packed with alternate picking acrobatics and light-speed hammer-on/pull-offs.