"People are talking about speculation that 38 points will be enough, but in the history of the Premier League it's always that magic number of 40," Bilic told in a news conference on Thursday.
"We are not panicking, but none of the teams, until mathematically, are safe. Maybe we have enough (points), but we can't be sure ... We're three games unbeaten, and of course the confidence is higher. It's related to the way we are training and the games we play."
Bilic was not sure who will start as the goalkeeper this weekend at the bet365 Stadium. Goalkeeper Darren Randolph has featured in 22 league games but his replacement Adrian kept a clean sheet against Everton last weekend.
"I had a couple of meetings with them individually and explained my decisions," the Croatian boss added. "Darren is a great professional, of course he is disappointed but he understood my decision.
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"He is training hard and waiting for his chance, just like Adrian waited for his."
West Ham skipper Mark Noble will return to the squad after serving his suspension while striker Andy Carroll is set to remain on the sidelines with a recurring thigh problem.
The London side will face Mark Hughes' Stoke who have picked up just one victory in their last seven league games.
(Reporting by Hardik Vyas in Bengaluru; Editing by Andrew Heavens)
