The Blues beat Middlesbrough 2-0 on Tuesday evening to reach the semi finals.
The Blues saw off Middlesbrough 2-0 at the Riverside in their quarter-final clash, with goals from Gerard Deulofeu and Lukaku seeing them through.
It was a highly accomplished performance from Roberto Martinez’s side as they managed to contain the home side to half chances at best.
It is the first time they have reached the last four of the competition since 1988, with only a two-legged tie now standing between them and an appearance at Wembley.
Lukaku though, says they must stay grounded as they continue to impress.
"We just have to work hard and keep doing what we have been doing. Today was a good result and we were 2-0 up and should have scored more,” he told Sky Sports.
"It is positive for us. The first goal was important but Gerard Deulofeu is doing well for us and I hope he keeps the level for us.”
"We are hungry, young players and want to improve game after game. We need to stay grounded and we want to be better."
Key to any potential progress to the final will surely be duo Lukaku and Deulofeu, who have formed a deadly partnership this season.
The Belgian now has 13 goals to his name in all competitions this season, with him second behind Jamie Vardy in the Premier League’s top goal scorer charts.
Deulofeu in contrast has been chief creator in the side, with six assists in the Premier League and three in the League Cup. In fact, no player has been involved in more League Cup goals than him this season.
Everton will be hoping the duo can be equally effective in their upcoming semi final clash.