The Russia international will be playing at a sold-out Old Trafford for the first time.
"Effectively it is a game for first place in the table, so it is like a final,' said the Russian international. 'It is probably the biggest game in the world on the day. I cannot say it is the most important one I ever played in, that is always the next one that is coming.," Zhirkov told chelseafc.com.
The 26-year-old has long been an admirer of the English game and had kept detailed cards on all of the big sides in the Premier League growing up in Russia.
"I don't remember much from the cards now, but last year they were the champions and they are a very strong team, which is the most important thing now," he said.
"I was at the Luzhniki Stadium in 2008 for the Champions League Final, it was a good game, two of the largest teams in the world playing, so it was more than worthy of a final.
"I didn't know then that I would be here, and I wasn't thinking about where I would be going. I have only been to Old Trafford to watch CSKA Moscow play there, so I have not played there yet, but every player would like to play at such a place."