In fact, a win is the only result that would give Chelsea real hope in the title race.
They are already ten points behind league leaders City, having succumbed to a second defeat of the season in midweek against Wolves.
Alonso said to the Evening Standard: " "We have to work hard, stay together and get back to winning as soon as possible.
"It's early to talk about this [being out of the title race], but if we lose to City we will be 13 points from the top and that is a lot of points [to make up]. But we just have to think about preparing well and not think about the table."
And added: It's a perfect opportunity for us to bounce back.
"It will be a great game and everyone will be very motivated to play. It is a chance for us to respond.
"Everyone is very disappointed after the Wolves defeat, but we have to get back to work in training and on Saturday be better as a side.
"Can I say what's going wrong exactly? Not really. We have to play more as a team.
"It is something that we have to analyse, the manager will have to, and we will try to improve as quickly as possible."