England midfielder Dele Alli (left) was taken off towards the end of the opening Group G game against Tunisia
Midfielder Dele Alli missed England training on Thursday as his thigh injury continues to be monitored before Sunday's match against Panama.
The Tottenham player suffered the problem during the 2-1 victory over Group G rivals Tunisia, although he managed to play for 80 minutes.
The 22-year-old tweeted on Wednesday that it was "a slight injury".
Meanwhile, manager Gareth Southgate has discarded his sling as he recovers from a dislocated shoulder.
The 47-year-old fell during a run near England's World Cup camp in Repino and was treated in a nearby hospital.
"The doc has made it clear punching the air is not an option," said Southgate, who jumped in the air celebrating Harry Kane's injury-time winner in Monday's win.
"I might not be celebrating any goals as athletically in future."
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Source: bbc.com