Rob Green believes question marks remain over West Ham's Joe Hart

A reflection can be seen of Joe Hart of West Ham United during the Premier League match between Chelsea and West Ham United at Stamford Bridge on April 8, 2018 in London, England.

Joe Hart has returned to the West Ham starting line-up of late.

A reflection can be seen as Joe Hart of West Ham United makes a save during the Premier League match between Chelsea and West Ham United at Stamford Bridge on April 8, 2018 in London,...

Former West Ham United goalkeeper Rob Green has told Sky Sports that question marks still remain over goalkeeper Joe Hart ahead of the World Cup in Russia this summer.

Hart, 30, has returned to the Hammer starting line-up to impress in recent matches, starring in his last outing as West Ham produced an excellent rearguard display to hold Chelsea to a 1-1 draw at Stamford Bridge.

England international Hart produced a multitude of excellent saves, keeping out Willian, Marcos Alonso and Olivier Giroud with a string of superb reactions as the Hammers secured a vital point in their fight for survival.

Joe Hart of West Ham United during the Premier League match between Chelsea and West Ham United at Stamford Bridge on April 8, 2018 in London, England.

But Green, who has since played for QPR, Leeds United and current side Huddersfield Town since leaving the Hammers in 2012, believes there is still doubt as to whether Hart will be England's number one - or indeed even in the squad.

"He's bounced back and he had a great game last week - I'm really pleased for him - but the question mark is still there," Green said.

"It's going to be a tough one for Gareth [Southgate] to work out. Maybe he has got ideas already but I think it's something he has to mull over, and the next few games could be critical.

"I think he said himself in the last international break that the shirt is up for grabs so every performance is key now."

Robert Green of West Ham United gestures to the fans during the Npower Championship Playoff Semi-Final 1st leg match between Cardiff City and West Han United at Cardiff City Stadium on May...

Hart, who remains on loan from Manchester City and is expected to start between the sticks against Stoke City on Monday, faces huge competition from Jack Butland and Jordan Pickford to be England's number one.

But with six Premier League games to play, former Torino loanee Hart could play himself into contention with a string of inch-perfect performances ahead of this summer's World Cup in Russia.

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