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England midfielder Jordan Henderson is a fitness concern for manager Gareth Southgate ahead of Wednesday's meeting with Croatia in the 2018 FIFA World Cup semi-finals. 

The Three Lions return to training on Monday, but Henderson's tight hamstring is said to be a concern, per Sky Sports. Southgate touched on the playmaker's hopes of featuring, per Metro's Coral Barry:

"We'll just have to assess people as we go. Hendo was one who was feeling tightness in his hamstring, which was why we made the change.

"We'll just have to assess the bodies. They've been through a lot. More the other night coming into today.

"But of course you get an accumulation of fatigue through a tournament, and that's why we took the decision we did against Belgium more than anything."

Despite the setback, Liverpool star Henderson appeared confident of featuring after injury analyst Ben Dinnery provided quotes from the player, who gave an update on his chances on Sunday:

The 28-year-old was substituted off for the first time at this World Cup during Saturday's 2-0 quarter-final win over Sweden, having played the full 90 minutes in three other matches and being rested for the Belgium defeat.

There was discussion in the build-up to the World Cup regarding Henderson's role in Southgate's side and whether he was an expansive enough midfielder for the job, but the omens point to his vital impact, per The Sun:

He and fellow Sunderland alumni Jordan Pickford—now at Everton—have both been crucial figures for England in their run to the semi-final meeting with Croatia at the Luzhniki Stadium in Moscow.

Writer Joel Rabinowitz highlighted the former national team captain's importance to the team after their quarter-final victory:

England have been fortunate to avoid much injury trouble in Russia so far, but Henderson's hamstring doubt throws up a potential curveball at the centre of Southgate's side.