David Moyes thinks the Africa Cup of Nations may have helped Didier Ndong and Lamine Kone find their best form.
The pair returned to the side on Tuesday night and made a big difference to the team in terms of energy and discipline.
Both had tough times in Gabon but Moyes thinks escaping the relegation battle for a month might have worked wonders.
He said: “Didier gave us a lot more energy in midfield.
“I think, like everyone else, there have been periods throughout the season where Didier didn’t play quite so well.
“We’ve asked so much of him, bringing him over from France, he doesn’t speak the language yet, so we really have to look ahead and say ‘can he keep improving’.
“But he came back from the Africa Cup of Nations looking fresher, having got away from the stress and the pressure of this league.
“Lamine the same, as well.”
Moyes is also hoping Darron Gibson can add some creativity and vision in midfield, but warned against burdening the Irishman with too much expectation.
The 29-year-old has only two competitive appearances for Everton to his name this season, the latter in the much derided Checkatrade Trophy.
Moyes said: “If I thought we could have bought a £20m central midfielder and brought him here, I would have done so.
“But ultimately it was unrealistic for two reasons – we didn’t have that kind of money to spend, and in the present situation I am not sure we could attract that level of player.
“So what I had to do, like we did with Victor Anichebe coming in, is find a way of bringing people in for not too much money but who can add something to us and help us get away from where we are in the table.”