He said: "On the way to the stadium to view the game on the big screen last night, just at the square at Alameda de Hércules, we took a seat to rest in the heat and I stood up to walk to the stadium. I only walked maybe 15-20 meters when I realised I didn't have my bag."
The Gers fan quickly took to social media to ask fellow supporters for help and he quickly found answers.
Chris added: "I heard reports on social media by lots of people that it has been handed into a pub but when I returned to the square, there are quite literally hundreds of pubs within a five-minute walking distance.
"So, I am going around looking for it but so far, I have been unable to locate it."
He is desperate to get the black bag back in time to catch his flight tonight.