Manchester United goalkeeper Sam Johnstone has agreed to extend his loan spell with Doncaster Rovers until the end of January, as reported by the club’s official Twitter account.

#mufc goalkeeper @SamJohnstone50 has extended his loan spell at Doncaster Rovers until 28 January. pic.twitter.com/U37ioAIVsX

— Manchester United (@ManUtd) January 5, 2015

The 21 year old has been with Man Utd since 2009, and in the six years since he joined, he has had loan spells with lower league sides like Scunthorpe United, Walsall, and Yeovil Town, who Man Utd beat 2-0 in the FA Cup third round yesterday.

This season’s spell with Doncaster follows on from last season, when he was also on loan at the South Yorkshire club.

Johnstone has also played at international level.

He has made appearances for English youth sides all the way up to Under-20 level, suggesting that he has considerable potential.

However, the mountain he’d have to climb to a first team place at Old Trafford seems insurmountable.

David De Gea is in the form of his life, and is not likely to be replaced by a young pretender any time soon.

He will stay with Doncaster until January 28.