England captain Joe Root wants his side to make the most of Australia being without Steve Smith in the third Ashes Test. (1:01)

Jason Roy has come through a concussion test following a blow to the head while batting in the nets on Tuesday, but will be assessed once more before he is cleared to play in the third Ashes Test at Headingley.

Roy sustained a blow directly on the stem guard when facing throwdowns from Marcus Trescothick. He was assessed both at the time - he was cleared to carry on batting - and again on Wednesday morning before training but will undergo one more test on Thursday morning before he is deemed eligible for selection.

Jason Roy receives treatment after copping a blow in the nets Getty Images

While he is thought highly likely to be declared fit to play, England will have Ollie Pope on standby should Roy display any symptoms of delayed concussion. If that happens, and Roy misses out, Joe Denly would be promoted to open the batting alongside Rory Burns and Pope would slot into the middle-order. Pope and Dominic Sibley were on unofficial standby during the second Test at Lord's in the understanding that Sibley would come in for a top-order batsman and Pope for a middle-order batsman.

In years gone by, it is probable the blow sustained by Roy would have gone largely unnoticed. But with concussions very much in the news and a growing awareness of the seriousness of the condition, the cautious approach taken by England here is likely to become the norm. Roy batted in training without any apparent discomfort on Wednesday.

"I'm pretty confident Jason's going to be fit," Joe Root said. "He's been monitored quite closely as you'd expect; there is a huge amount of attention around concussion at the minute. He's undergone a couple of concussion tests so far and scored really well. So as it stands I fully expect him to be fit and ready to go.

"You can only make a change if it happens within a Test match not if it happens prior to it so, with that in mind, we will have to be absolutely sure Jason is fit and ready to go, but we are fully confident he will be."