Eden Hazard admits a return to the Champions League has complicated Chelsea's defence of their Premier League title this season.
The Blues lie fourth in the table after 26 matches, 19 points adrift of runaway leaders Manchester City, and head coach Antonio Conte's future at Stamford Bridge is in serious doubt after two humiliating defeats in succession against Bournemouth and Watford.
Conte and several of his players have pointed to a relentless and at times unfavourable schedule as a factor in Chelsea's recent slump, and fatigue has manifested itself in a wave of injuries that has swept through the squad.
Chelsea's crisis has come at the worst possible time with a Champions League round-of-16 tie against Barcelona looming large on the horizon, and Hazard told ESPN FC that European commitments have made life harder.
"I think the Premier League is difficult," he said. "It's hard to win every year. Last year we didn't have the Champions League. This year we have less time to be ready for the games. Every week there are three games."
The gap between City and Chelsea was just three points when the two sides met at Stamford Bridge in September.
Conte's men, having overcome Atletico Madrid in a hard-fought Champions League group stage match little more than 48 hours earlier, lost Alvaro Morata to a hamstring injury after only 35 minutes and eventually slipped to a 1-0 defeat.
Chelsea's title defence has also suffered as a result of squad turnover. Diego Costa and Nemanja Matic departed in the summer while six new players arrived.
The headline purchases were Morata and Tiemoue Bakayoko, but the Spain international has struggled for goals after a promising start to his Blues career and the Frenchman has been inconsistent.
"We changed a couple of things, we lost players, we brought some new ones and every year is different," said Hazard, who was speaking at a Nike event in London to mark the 20th anniversary of Nike's Mercurial football boot.
"That's why we love football -- if there is only one team that wins it would be boring. That's why football is special. You never know what's going to happen, especially in England."