Jose Mourinho's men have been a shadow of the side that so impressively won the title last term, having lost half of their opening eight Premier League fixtures.
It leaves the west Londoners 16th in the standings and 10 points behind leaders Manchester City, making this weekend's home clash with Aston Villa important for both embattled sides.
Cahill expects to be fit to face his former club after a back complaint during an international break which saw Branislav Ivanovic and Nemanja Matic forced off through injury playing for Serbia.
"I don't know how bad their injuries are, hopefully not too bad," Cahill said of the pair - the latter of whom returned for their defeat to Portugal.
"My injury is okay.
"Luck's not on our side at the minute, but you have to make your own luck in terms of performances at the club.
"That's something I'm determined to put right and I'm sure everyone else is.
"It's not a nice feeling at the minute and one we don't want to have for very much longer."
Cahill returned to Chelsea earlier than many of his team-mates after being rested for England's final Euro 2016 qualifier in Lithuania.
The centre-back watched the Vilnius triumph from home and returns to club action buoyed by the experience of leading his country out for the first time, captaining the Three Lions to Friday's 2-0 defeat of Estonia.
"It was an amazing feeling for me and my family and a moment I'll never ever forget," Cahill said.
"But once I knew I was captain I wanted to make it work and to lead them to a positive result and thankfully it went that way.
"I thought I played well, and the team played well
The most important thing was that we won so a good night."
Source : PA