Despite being the first-choice goalkeeper at the club for the past decade, Cech's place is believed to be under threat from the Belgian, who has spent the past three seasons on loan at Atletico Madrid.
However, Cech claims that his attitude will not change if Jose Mourinho chooses to keep Courtois at Stamford Bridge for the next campaign.
"If, on the first day of pre-season, Thibaut Courtois is here, he is here," the 31-year-old told the Daily Mail. "If he is not, he is not. It does not change anything. I will still have to do better than whoever else is here, to keep my place.
"If he comes back and he's better than me, credit to him, well done to him, but who knows? I'm not afraid.
"I'm not a fool to think I've been here 10 years and I'll be here another five, just because."
Reports on Thursday suggested that Courtois could sign a new loan deal with Atletico.