England's keeper conundrum explained

Burnley's Nick Pope has forced himself into Southgate's reckoning with a fine season and is part of a four-strong group of goalkeepers for England's final World Cup warm-up friendlies against the Netherlands on Friday and Italy on March 27 before Southgate names his World Cup squad.

Here, AFP Sports looks at the contenders to be England's number one in Russia:

Joe Hart (West Ham)

He is, by a distance the most experienced of the quartet of 'keepers in Southgate's squad with 74 caps, but his career has been in free fall since England's last major tournament.

Hart was at fault for Iceland's winner as the Three Lions crashed out in the last 16 of Euro 2016, as a familiar weakness down to his left was exposed by Kolbeinn Sigthorsson.

Despite being ousted from Manchester City by Pep Guardiola shortly after the Catalan's arrival, Hart has remained Southgate's number one during unconvincing loan spells at Torino and West Ham.

However, having played in just one of the Hammers last 16 Premier League games after being dropped, Hart's is hanging onto the number one jersey by his gloved fingertips.

Jordan Pickford (Everton)

Pickford has had an inconsistent first season at Everton after sealing a £30 million move from Sunderland to become England's most expensive goalkeeper ever.

However, at 24, he has time on his side. Despite just one senior international cap in a 0-0 draw against world champions Germany in November, he has plenty of international experience at under-21 level.

A former under-21 manager, Southgate values the experience gained in youth international tournaments and described Pickford and Swansea defender Alfie Mawson as "the standout performers" of England's run to the semi-finals of last year's under-21 European Championships.

Jack Butland (Stoke City)

But for a horrific ankle break suffered as England won in Germany almost exactly two years ago, Butland may even have displaced Hart in time for Euro 2016.

Instead, Butland didn't return to first team action until April 2017 and has made only two England appearances since, including his only start in a competitive international last October.

Despite a costly own goal in a 1-1 draw at Leicester last month, Stoke manager Paul Lambert branded Butland the "best goalkeeper in Britain."

Like Pickford, he also has a wealth of international experience at youth level, including two under-21 Euros.

Nick Pope (Burnley)

Pope is the new boy at international level on the back of a brilliant season at Premier League surprise package Burnley.

The 25-year-old admitted on Tuesday he never believed he would make an England squad after being released by Ipswich Town as a 16-year-old and spending the majority of his career trawling through the lower leagues.

"If we have a problem with any of our other goalkeepers it's important that we find out more about Nick, and form-wise he deserves to be in the squad," said Southgate last week.

That seemed to suggest Pope's lack of experience makes him a back-up option.

But he is the man in form. Only Manchester United's David De Gea, widely regarded as one of the world's best 'keepers, has a better save percentage than Pope this season.