Wales lock Alun Wyn-Jones was in danger of being re-named "Alun-Sin" Jones after coach Warren Gatland said his reckless yellow card was the cause of his side's 30-17 Six Nations loss to England.
Jones was sent to the sin-bin shortly before half-time in the teams' tournament opener at Twickenham here on Saturday for a blatant trip on England hooker Dylan Hartley that left referee Irish referee Alain Rolland with little option but to dismiss the second-row for 10 minutes.
In Wyn-Jones's absence, England scored 17 points to take the score from 3-3 to 20-3 in their favour.
Although Wales fought back with tries from prop Adam Jones and outside centre James Hook, the damage had been done.
When blindside flanker James Haskell, the man-of-the-match, scored his second and England's third try from five minutes from time, Welsh dreams of a fourth straight Six Nations win over England ended.
For Gatland, whose first match in charge of Wales was their 26-19 win at Twickenham two years ago, a victory that sparked a Six Nations grand slam, defeat was tough to take.
And the New Zealander was in no doubt about who to blame.
"We are frustrated and disappointed," Gatland told reporters.
"We felt that was a game that has slipped from our grasp. The yellow card has cost us 17 points - it was one of those things, stupid.
"It was massive. Sometimes those things are very, very costly, and it was for us today," he said.
"We had stressed discipline over the past two weeks and talked about giving nothing soft away, and it is frustrating we have done that.
"He [Jones] has made an impulsive decision, and hopefully it is a learning experience for him and he doesn't do it again."
Gatland added he hadn't need to give the 24-year-old law student a piece of his mind as Wales defence coach Shaun Edwards, the former Great Britain rugby league international, had done it for him by saying: "I just hope you never do that again in your career, it was stupid and probably cost Wales the game."
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