Crosas, 20, said: "I know derby matches are special because I spent so long at Barcelona watching games with Real Madrid.
"It was the game everyone wanted to play in.
"I was no different but the closest I came was last December when I was in the squad.
"I thought I might get a seat on the bench but I had to settle for watching from the stand.
"Being involved in those games is special and even if I'm not playing for Celtic against Rangers I will give my all as a squad member to help them win.
"But nothing can beat playing. I can only imagine what it would be like to play in a derby and when I do imagine I get quite excited.
"I've seen quite a few Celtic games on TV and was always impressed by the atmosphere but nothing beats the real thing."
Crosas added: "I spoke about the atmosphere at Celtic before I came to the club but I never imagined how great it could be.
"I was delighted with the way the fans took to me as I came off the bench."
In other news today the SPL has announced that it will extend the Transfer window by one day. It should be noted that this is not at the request of Rearangers but due to the fact that the last day of August falls on a Sunday, which would complicate any last-minute deals.
Yours in Celtic
Clydebuilt