Chelsea vs Everton: Guus Hiddink unsure of Chelsea's reason to sell in-form forward Romelu Lukaku

Chelsea manager Guus Hiddink has admitted a hint of surprise with regards to the club management's decision to sell Romelu Lukaku to Everton before the start of the 2014/15 season. It was Jose Mourinho's decision to let go of the striker following the arrival of Diego Costa from Atletico Madrid.

The Belgian international spent the 2013/14 campaign on loan with the Toffees and was expected to be drafted back into the first-team fold at Stamford Bridge owing to his impressive performances for Everton. He scored 15 goals in 31 appearances helping the Goodison Park outfit to fifth place in the Premier League.

The Portuguese manager, however, decided that he was surplus to requirements and allowed him to join Roberto Martinez's side on a permanent basis for a club record fee of around £28m ($40m). The former Chelsea boss revealed that the striker's insistence on wanting a regular starting role was the reason he was allowed to leave the club.

Hiddink has praised the former Anderlecht forward ahead of the reigning Premier League champions' clash against Everton on Saturday 16 January and believes he has become a very "dangerous player" over the last couple of seasons. Lukaku has scored 15 goals in 21 Premier League appearances thus far this campaign and will surely be looking to pile on the misery when he faces his former club at Stamford Bridge.

"Lukaku developed himself, especially last year. He is a very dangerous player. It is difficult to make that judgment, how he performed when he was here, and I don't know the reason why he was sold, but it's up to the management, you have to ask them, why they would do so," Hiddink said, as quoted by The Guardian.

"He has become a strong player and it is nice to see players develop. He's one of the top strikers. Normally strikers who are not top in the league, they might get a little frustrated when they don't score. But he is very cool and if he doesn't score one game, then the next game he is taking the chances and that's what makes him a good player," the Dutch manager added, as quoted by Goal.com.