Chelsea could face another disappointing season if their players don't learn to work as a team, new manager Antonio Conte said.
The Italian was speaking after his side's 3-2 defeat against Real Madrid.
The Blues fought back from 3-0 down to close the gap to only one goal but it wasn't enough as the Spanish giants closed the game with a victory.
"It is not easy to play this game against another great club after only two days of rest and a flight of four-and-a-half hours," Conte said.
"I knew the team was a bit tired.
"But today I think this match was very important for us, because after this game it is clear we need to work together always, without the ball and with the ball.
"If we think we can't work together when we haven't the ball, it is not possible for us and we risk repeating a bad season.
"Today we weren't a team in defensive situations. It is important to understand this because in the last game I appreciated that we were lot.
"Then I thought we could improve when we had the ball. Today we were better with the ball but bad without the ball.
"It is important to keep concentration and to work together.
"I know it is fatiguing to work without the ball but if we stay compact, like against Liverpool, we can win. If we lose this compact, if we think one, two or three players don't want to work without the ball, it is possible we see another bad season."