The Brazilian defender netted a stoppage-time winner for the Blues to leave them on the verge of reaching the Europa League final, but is urging his team-mates to be cautious
Luiz's late winner gave Chelsea 2-1 win over Basel in Switzerland and the two away goals left the Blues firmly in the driving seat ahead of the return clash at Stamford Bridge.
Many believe the second goal gave Basel too much to do in the second leg, but Luiz is wary of a backlash from the side that knocked out Tottenham in the last round.
"It was important to score two goals here because Basel are a very good team and their philosophy to play good football is amazing. It is difficult to win here," he said. "It is amazing that we scored the second goal with the last kick but we have the second leg and we need to keep our minds strong because it will be another difficult game for us.
"I didn't see the penalty but if the referee gives a penalty then it is a penalty. A 1-1 would have been okay but 2-1 is better. We are so happy with this.
"I want to get to the final this year and to do that we have to win the second leg or draw so it is not finished."
With the race for a top four spot set to go down to the wire, critics have suggested the Europa League may not feature as high on Chelsea's list of priorities as it could do, but Luiz dismissed this claim.
"The competition is so important for us," he insisted. "I want to win another European title for my career and for Chelsea."