Chelsea captain, Cesar Azpilicueta has reacted to his side's 2-1 win over Malmo in the UEFA Europa League round of 32 first leg tie on Thursday night.
Goals from Ross Barkley and Olivier Giroud handed Chelsea all three points against Malmo at Swedbank Stadion.
However, a goal from Anders Christiansen was not enough to give the hosts a point against Sarri's side.
Azpilicueta said it was 'frustrating' for Chelsea to concede a goal against Malmo, adding that the Blues should have kept a clean sheet against the Swedish side.
"It was a tough defeat last Sunday, but we are in the knockout stage and it's important to start well," Azpilicueta told BT Sport.
"We had chances to have a more comfortable result, but they scored and there is still a lot to play for next week.
"In the second half we had whole control of the game and had a lot of chances. It's frustrating to concede a goal and not to have a better result. It's still all to play for.
"This tournament is very important, we are fighting for trophies and to be in the top four. We are in the EFL Cup final [against City] next week, every trophy is important."
Chelsea will tackle Manchester United in the FA Cup at Wembley on Monday night in their next fixture.