Andy Robertson trains as Steve Clarke calls up Max Johnston for Scotland's World Cup qualifiers

Andy Robertson has eased concerns regarding his fitness by taking part in training with the Scotland squad ahead of their crucial double-header this week.

Steve Clarke has called up Derby County right-back Max Johnston to bolster his defensive options for the upcoming World Cup qualifiers.

The national team play Belarus and Greece in a Hampden double header this week as they look to take a step closer to the tournament being held in North America next summer.

Johnston, who earned his first cap in a 1-0 win over the Greeks earlier this year, was initially left out of the squad with Aaron Hickey and Anthony Ralston being the preferred options at right-back.

But the 21-year-old has now been added to the squad to bolster the defensive options amid doubts over the fitness of Robertson, who appeared to pick up a knock in Liverpool’s defeat to Chelsea at the weekend.

However, the captain looks set to play a part after taking part in full training on Wednesday.

Johnston has four international caps and came off the bench for the last 20 minutes of the draw with Denmark before starting the win over Belarus in Hungary.

He joined English Championship club Derby from Austrian side Sturm Graz in the summer.