Since announcing his departure from Judas Priest in 2011, guitarist K.K. Downing had not stepped foot onstage until joining Ross the Boss at Bloodstock Open Air in the United Kingdom yesterday (Aug. 11).

Ross the Boss, who was a member of Manowar's classic lineup, performed seven Manowar songs before welcoming Downing to the stage for the final four songs of the night — first, a cover of Judas Priest's rendition of Fleetwood Mac's "Green Manalishi (With the Two-Prong Crown)" followed by three Priest originals in "Heading Out to the Highway," "Breaking the Law" and "Running Wild."

Watch fan-shot video of the four-song performance featuring Downing's first public concert performance in a decade (also the first in his 60s — he'll be 68 in October) below.

Downing didn't don the iconic leather and studs look that is synonymous with Judas Priest -- an image he claims to have devised on his own as outlined in his memoir, Heavy Duty: Days and Nights in Judas Priest. Instead, he wore a long-sleeved black shirt, but his guitar strap still bore the word "Priest" like it did back in the day.

Last year, Downing made headlines when it was revealed that he was selling his rights to over 130 Judas Priest songs. He's also more recently engaged in a war of words with his former bandmates, agitated that he was not invited to return to Judas Priest upon Glenn Tipton's live retirement due to complications from Parkinson's Disease.

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