After grabbing a valuable draw against Leicester on Saturday, the Potters are in 19th, but just one point from 16th placed Southampton.
Lambert's side will travel to Southampton on Saturday in a do-or-die clash. And the Scotsman knows his players will be up for the fight.
"We seem to have the belief going into games and the way we are playing I don't fear anybody," he observed.
"If we'd have had more points (v Leicester) I don't think anybody would have begrudged us them.
"I think you can talk about tactics all day long and talk about systems and formations, but sometimes football is what's in your stomach. You want to go and perform, throw your body into things and have that drive and willingness to be committed. We have that.
"Since I've been here, they seem to be bang at it. The level has been really good and you can see it from the supporters' reaction. The supporters were brilliant again."