Segundo Castillo in reckoning for Everton's West Ham trip

But the temptation to go for a 4-4-2 formation may be resisted for an away fixture with a Hammers side that would overtake Everton in the table if they claimed three points.

A return to one up front could leave Everton having to push Leon Osman further forward and abandon the holding role he has adopted in recent games, which has allowed Fellaini to push on and get among the goals.

And with Moyes confident that Castillo is close to the level he needs to reach to make a return after a frustrating spell on the sidelines, he is under consideration.

The Ecuador international hasn't played a first team game since September after an initially promising start to his one-year loan, including a goal in the UEFA Cup tie with Standard Liege.

He was injured while on internat-ional duty last month and has struggled to regain full fitness, but did complete 90 minutes for the reserves in their 2-1 defeat to Blackburn earlier this week.

Having a player who can break play up in front of the back four is also one of Moyes's priorities due to the tightening-up of his side's defensive work in recent games.

It's more than four hours since Darren Fletcher was the last player to break the Everton rearguard, which has enjoyed back-to-back clean sheets.

And Moyes feels the return to sharpness, both mentally and physically, of centre-back Joseph Yobo has been integral to that improvement.

The Nigerian had a disrupted build-up to the new campaign following a gruelling World Cup qualifying schedule and the kidnapping of his brother - but Everton's woeful shortage of numbers meant he was pressed into action before he was fully prepared.

"Joe has started to play much better in the last couple of weeks," said Moyes. "He had a long summer playing for Nigeria then he had those problems with his brother.

"An issue like that is bound to have an impact and prey on your mind but everything turned out well and I think Joe has refocused on things now."