Adrian Grenier Says Goodbye to Entourage and His Costar, Arnold

Courtesy Adrian Grenier

updated 07/08/2011 AT 1:00 PM ET

originally published 07/08/2011 AT 2:45 PM ET

After eight seasons, HBO’s Entourage has wrapped filming, and the show’s stars have been getting emotional about the end.

Adrian Grenier has shared photos from his last days on set, including a shot with his canine costar, Rocky, who played the Entourage crew’s beloved Rottweiler, Arnold.

“Saying my goodbyes to ‘Arnold’ (Rocky) and thanking him for 8 great years of loyal service!” he wrote on Facebook.

“I think he knows Entourage is coming to an end – dogs always know,” Grenier added. “(And I kinda look like a dog in this too. Ruff Ruff.)”

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