Ryan Harris said Peter Siddle's "unacceptable" no-ball that saw Jonny Bairstow reprieved at Lord's could have cost Australia the Ashes.
Bairstow had made 21 on the first day of the second Test on Thursday (July 18) when he was clean bowled by Siddle, with England then teetering on 171 for 5. But Bairstow was told to wait on the outfield by umpire Kumar Dharmasena as he asked third umpire Tony Hill to check for a front foot no-ball. After several minutes' study, Hill decided Siddle had over-stepped, albeit fractionally.
England's fifth wicket duo - Ian Bell and Bairstow - went on to add a hundred more runs before Bell, who made 109, became the fifth man out with the score on 271.
Bairstow himself pressed on to 67 out of an England total of 289 for 7 at close of play.
Harris, recalled after Mitchell Starc was dropped from the Australia side that lost the first of the five-match series by just 14 runs at Trent Bridge last week, said Darren Lehmann, coach of the team, and Ali de Winter, the bowling coach, had repeatedly emphasised the importance of avoiding no-balls.
"Ali de Winter and Darren are strict on us in the nets," said Harris, who finished the day with 3 for 43 in 20 overs without having bowled a single no-ball. "Once we are off our long runs we are not allowed to go over. There is no excuse. The line is there for a reason and it is unacceptable."
As England hold the Ashes, they only have to draw this series to retain the urn whereas Australia need an outright win across the five Tests to regain the Ashes.
"It cost us a lot of runs today and potentially it could cost us the Ashes," lamented Harris. "We were pretty disappointed. Darren was not very happy when we went in. You just can't afford to have to take 11 wickets or 12 wickets. It's as simple as that. It was probably the only one he (Siddle) bowled."
Indeed it was the lone no-ball Siddle delivered in what turned out to be a wicketless return of 12 overs for 48 runs.