Martinez backs Chelsea target John Stones to bounce back from slump
Everton manager Roberto Martinez has backed John Stones to bounce back quickly from his first real shaky spell at the club.
The England centre-back has endured a tough January by his usually high standards with a number of noticeable errors and lapses.
He was withdrawn after 77 minutes of their Capital One Cup semi-final exit to Manchester City after a lapse of concentration allowed Sergio Aguero to score what turned out to be the winner, having contributed to Swansea's opener the Sunday before with a poorly-judged backpass.
Stones' miscalculations have directly led to eight goals for the season, with seven of those in the last three months, and he was left on the bench for the FA Cup fourth round win at Carlisle.
But Martinez has no doubts about recalling the 21-year-old, who was the subject of a failed £38million bid by Chelsea last summer, to the centre of defence for Wednesday's visit of Newcastle as he is no longer required to cover for Seamus Coleman at right-back.
"You are talking about a player of 21 who has played over 92 percent of the minutes in the league, which is a phenomenal return." he said.
"When you reach the level of John Stones you are going to get that scrutiny and John is strong enough mentally to understand that is going to be his role in professional football and representing England for the next 15-20 years.
"John is such a strong-minded boy and has been through a lot over the last eight months but has done it professionally. In those moments you need to know who you can trust and you need fair criticism and fair evaluation of your performances.
"It is not an issue."
While Stones has struggled in recent weeks his England team-mate Ross Barkley has flourished.
The 22-year-old had his own issues with form last season but has come back stronger this campaign with a series of impressive performances.
He is set for his 100th Premier League start against the Magpies and Martinez expects the midfielder to play a pivotal part in the remainder of the campaign.
"Ross has been now filling an important role in the team for a long time but this season he has taken his performances to a different level," added the Toffees boss.
"He is someone who can understand different roles on the pitch and his technical ability and physical strength is there to be seen but I think this campaign we have seen a very composed Ross Barkley, someone with incredible decision-making and maturity.
"To reach that milestone at 22 is an incredible return and is something which will be difficult to be matched."
Deadline-day signing Oumar Niasse, a £13.5million signing from Lokomotiv Moscow, will not be eligible until Saturday's trip to Stoke but Martinez expects the Senegal international to adapt quickly.
"He is a player we have been tracking for a long time, the first time we saw him was in the first week of September and since then we have been very close trying to find out about his character," he added.
"He has a very specific family situation as his wife is English and from the north west and he has been following our team and the way we play and it was a real conscious desire to join us and that has been important.
"We didn't think he would become available but when we saw he was we moved very quickly.
"It was a sign of being precise in what we wanted; we moved two players from the first-team squad (Steven Naismith was sold to Norwich and Aiden McGeady loaned to Sheffield Wednesday) and we brought in a 25-year-old who has been successful in two European leagues.
"He is not back-up for anyone, he has his own ability and is someone who can stretch defenders and can cope with the physicality of the Premier League."