Gary Cahill says Chelsea's players are "not robots" and cannot be expected to perform every week, but is confident of an upturn in their flagging fortunes.
Monday's 2-1 loss at Leicester City was the champions' ninth defeat of the Premier League campaign, leaving Jose Mourinho's side just a point above the relegation zone.
But defender Cahill feels the London club's form – which stands in stark contrast to their title-winning season last time out – is part and parcel of the changeable nature of football.
"There are some great memories and I don't think we should forget the manner in which we won the Premier League, leading from the start, which was an unbelievable achievement for everyone at the club," he told Chelsea magazine.
"The flip side, as always with football, is that it's a game of two halves – and we've had a difficult period. Last season was fantastic, this season has been tough, but we're looking to turn that around. We're working hard to make things right.
"Not every single minute of your career will go well, individually and collectively, and not every season will go how you want it to, but it's how you react to that.
"You're not a robot, you're not going to be nine out of 10 every game.
"But when things aren't going well, you work even harder and look for a reaction. I'm sure we'll turn it around."
Chelsea, who will face Paris Saint-Germain in the last 16 of the Champions League, host fellow strugglers Sunderland on Saturday.
