Chelsea ace Eden Hazard admits he's struggling through the worst moment of his career.

Last season's PFA and Football Writers' player of the year has not been the same influential force and a string of disappointing performances saw him dropped from the side to face Porto in the Champions League last month.

"This is perhaps the most difficult period of my career. There are always ups and downs. I'm not certain what the problem is," he said.

"But we have to keep working hard to improve. It's always good to spend time with the national team, and even more so when things aren't going well for your club.

"I know I can do better. I have to be able to help the team win."