David Luiz was left frustrated in Chelsea's defeat to Liverpool.

Friday night marked Luiz's 'second debut' for the Blues.

"We controlled the second half but we couldn't get the second goal," Luiz told Sky Sports.

"I'm very happy to be here again. It's very important to play these games, the best kind of games in the world.

"I'm a bit sad because we didn't start how I wished.

"We need to improve."