Justin Langer defended Australia’s decision to let Steve Smith resume his innings on the fourth day at Lord’s just 40 minutes after being felled by a sickening blow to the neck from a Jofra Archer short ball.

The Australia coach admitted the incident brought back memories of Phillip Hughes, who died in November 2014 after a bouncer struck him behind the ear during a Sheffield Shield game in Sydney.

Smith had already taken a nasty blow to the forearm and underwent three concussion tests in the aftermath of the second knock: one on the field and two in the dressing room after initially retiring on 80.

But with those checks passed and personal assurances given, Langer was comfortable with his premier batsman being allowed to bat on.

Speaking after the close, by which time Smith’s arm had also been cleared of a break, Langer said: “You never like seeing your players get hit like that and there’s obviously some pretty rough memories. There was no fun in it.

“He passed all of the tests then he came back in the change room and he had a bit of a smile on his face. He was more worried about his arm actually – his arm was sore.

“He wouldn’t have gone out there unless we thought he was OK. We asked him over and over again. I asked him behind closed doors two or three and times and in front of the group. What else do you do? The medics cleared him, he wanted to get out there.

“As is the protocol, he’ll have another test in the morning so there’s no residual concussion. He’ll have that test and I suspect he’ll play the game out now.”

Smith, who fell for 92 amid a skittish resumption to his innings, does not wear the StemGuard add-on that became prevalent after Hughes’ death, with the extra layer of padding for the neck area not currently compulsory.

Langer said: “He doesn’t feel comfortable using it but he might rethink it now after seeing what happened today. The players have a choice but I wouldn’t be surprised if they become mandatory in the future.”

Players on both sides were rattled by the deliveries that struck Smith, inflicted during a fiery eight-over spell from Archer after lunch that demonstrated why the 24-year-old fast bowler is so highly rated.

He averaged 89.9mph on the speed gun and hit 96.1mph at one stage, with Chris Woakes, who eventually removed Smith lbw, in awe of the debutant’s performance and the extra bite he has given.

Woakes said: “You want Ashes cricket played hard and tough but you don’t wish injury on anyone, regardless of the situation of the game.

“It took a serious spell of bowling from Jofra to get Steve out of his bubble because so far this series he’s been incredible. It was serious pace. I haven’t been on the field when someone has bowled that fast consistently.”