What a difference a week can make in football. Seven days earlier, Evertons season plumbed new depths of frustration when they surrendered a two-goal lead in a 3-2 home defeat to West Ham United - but Goodison Park was rocking with renewed optimism on Saturday evening as the Blues booked their place in the semi-finals of the FA Cup with a 2-0 victory over Chelsea. Not for the first time this season, Romelu Lukaku was the oppositions downfall. The prolific Belgian opened the scoring against his former club in the 77th minute with a superb solo effort that will measure up as one of the goals of the competition. After tanking through the Chelsea defence to draw first blood for the hosts, Lukaku put them to the sword with eight minutes left to play, narrowly avoiding the offside trap to slot the ball beyond Thibaut Courtois in the away goal. It was a fiery quarter-final and tensions boiled over in the latter stages, with both sides finishing the contest with ten men. Diego Costa received the first red card of his Chelsea career after picking up a second yellow for his part in an altercation with Gareth Barry. The Everton midfielder later received his marching orders for a second bookable offence. With Everton just two wins away from their first silverware since 1995 and the Premier League champions season in tatters, here are six things we learned at Goodison Park.