Roberto Martinez has lauded the form of James McCarthy as Everton go in search of a sixth win in seven Premier League matches when they make the trip to relegation-threatened Aston Villa.
McCarthy, whose future at Goodison Park has been the subject of persistent speculation, spoke this week of being "let off the leash" after being afforded more freedom to get forward.
His manager has been impressed with the results, as McCarthy has netted in recent 3-0 home wins against Newcastle United and Manchester United.
"James McCarthy is insurance for me," Martinez said. "He gives you fantastic balance and in the last six or seven weeks we have allowed him to have a different role.
"He is getting a little bit higher up the pitch. He's been very effective. It's something quite new and he is enjoying it.
"James McCarthy is such a talented, young player that he could adapt to anything he would like to be. It's a great strength to have a player like him that can be so flexible."
Everton's impressive form has lifted them well clear of the relegation battle that they once looked in danger of being dragged into.
A top-half finish is now on the cards, with Everton sitting 10th, but they will have to continue to make do without Bryan Oviedo, who fractured his fifth metatarsal in training this week. Steven Pienaar (muscle fatigue) is also doubtful.
Villa, meanwhile, received a boost on the fitness front as Alan Hutton returned to training following an ankle injury, though Gabriel Agbonlahor (hamstring) remains sidelined.
Manager Tim Sherwood said the full-back will undergo a further assessment on Friday before a final decision is taken on the Scot's involvement.
Sherwood was left fuming at what he deemed a questionable offside call given against Villa in the 3-2 loss to Manchester City last time out.
The FA Cup finalists, who had battled back from 2-0 down to drawl level at the Etihad Stadium, saw top scorer Christian Benteke break clear, only to be flagged offside just before being brought down by City goalkeeper Joe Hart.
Their frustration was compounded when Fernandinho won it for the hosts at the death and Villa are just two points above the drop zone, leaving them needing a marked improvement on the display that saw them beaten 3-0 at Goodison Park in October.
That result made it eight games in a row in which Villa have failed to beat Everton, who have only failed to score in one of the last 15 meetings between the sides.
