The Blues Captain has admitted Alvaro Morata’s injury dampened Chelsea’s hopes against Manchester City.
Morata, who has hit the ground running since joining from Real Madrid, limped out of the Premier League clash on 34 minutes with a hamstring problem.
Chelsea were left without a recognised centre-forward on the pitch after Antonio Conte decided to send on Willian.
And Blues skipper Cahill believes they were impotent in attack without Morata leading the line.
“You look at the way he has started his career at Chelsea and it was a huge blow for us to lose him early in the game,” Cahill said.
“It affected elements of the game for us. His hold-up play as well as his finishing has been fantastic.
“Tactically we were frustrating them early on. We defended well and we’d win the ball at the back but by doing that we had a lot of men in our own third so it was difficult to break out.
“We’re used to breaking out very fast so when we did turn the ball over we had a lot of numbers in our own half. They made it tough for us and we did a lot of running.
“Obviously Willian and Eden are unbelievable on the ball, but size-wise they are small so it’s difficult to play high balls up to them.
“There’s no doubt losing Alvaro was a big blow.”