U.S. national team goalkeeper Tim Howard heals fast. Real fast.

The Everton ‘keeper, 35, went down with a calf injury on Boxing Day during the Toffees’ 1-0 defeat to Stoke City and has not played since.

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However ahead of the Merseyside derby on Saturday (Watch live, 12:30 p.m. ET on NBC and online via Live Extra) Everton manager Roberto Martinez has revealed that Howard is back in training ahead of schedule but will not be risked this weekend against Liverpool.

“Tim is back in training,” Martinez confirmed. “He feels strong and ready but the medical advice is to give him another week to make sure he is fully healed. We won’t take any risks. But it is incredible how quickly he has recovered and how well he has done in training.”

The initial diagnosis said Howard would miss at least six weeks, but he is back training within five.

Everton have struggled for most of the campaign defensively and have leaked 34 goals so far this season but they’ve shored things up at the back in recent games and have conceded just once in their last three matches and are five games unbeaten.

Young Spanish ‘keeper Joel Robles has looked shaky at times but has got into the groove of late and Martinez has no need to rush Howard back from injury.

That said, the USMNT star is still first choice for the Toffees and could be in line to make his comeback on Feb. 11 against Chelsea at Stamford Bridge but is more likely to aim for the home game against Leicester City on Feb. 22 to make sure his left calf has healed fully.

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