The Blues hammered Rovers 5-1, with Cucurella getting on the scoresheet.
"We are very happy because we know these games are never easy," he later told the club's website.
"We try in every game to have new ideas or different positions to attack the other team. We do a lot of work in training and then I try to do my best on the pitch. It’s about time and it’s a process."
Chelsea hold a 100 per cent record in the competition and Cucurella also said: "Sometimes we had long travel, but we showed every week that we tried to do our best. We practised our good football because we wanted to win in front of our fans. We finished well and we need to continue in this way.
"We know this competition is tough and we wanted another win tonight. We’re happy to get through this stage."
Of his own form, he added: "I’m very happy.
"I think in my first season it wasn’t easy but I tried my best, worked hard and waited for my moment. Now it’s a good moment for me and the team.
"I think the manager and my team-mates have given me a lot confidence and I tried to help the team always. We’re really happy and we’re trying to continue in this way. It’s a long season but we are ready to do good things."
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