Hard-headed Gatland opens the way for Roberts debut

Roberts, 21, will make his Test debut against Scotland at the Millennium Stadium on Saturday after Mark Jones was dropped following his performance at Twickenham.

More surprisingly still, there was also no place in the squad for loose forward Alix Popham, who impressed many observers with his impact off the bench against England but has been scalded by Gatland for a lack of discipline at the breakdown.

Victory at Twickenham was Wales' first in 20 years - but the euphoria within the squad was short-lived as Gatland and Shaun Edwards quickly delivered a blunt appraisal of their performance. "The players were a little surprised how critical we were of the individuals' performances," said Gatland.

"We enjoyed the win, but 24 hours later we were straight back to business.

"Mark has been given a few things to work on. He made a couple of defensive errors and turnovers.

"Alix gave away a couple of penalties, one of them should have been a yellow card, and defensively he made a couple of errors.

"The message at this level is: 'You have to be accurate'. Unless we criticise and point out faults, how do you get better? "You can't just say to the players: 'Fantastic, well done, pat on the back and now let's train'. You need to improve them from week to week.

"I expect those players who missed out to be disappointed. It is how they respond to that. The reaction is crucial. You just have to remind players of that.

"I am sure those players that have missed out will go away, work harder and come stronger for it."

Under the previous regime, the Wales players had privately complained they were not being challenged enough in training and life appeared too comfortable.

That is no longer the case. The intensity of the sessions under Gatland and Shaun Edwards is far higher than it was and the direction is clearer.

Wales captain Ryan Jones said: "A few individuals took a fair bit of flak, the majority of us took a fair bit of flak.

"We are professional people and it is not all high fives. We have been honest behind closed doors. We can't afford to rest on our laurels.

"We only won one game last season and that was against England. One game doesn't make for a season."

The other two changes made by Gatland were as expected, with Tom Shanklin preferred to Sonny Parker at outside centre and lock Ian Evans replacing his injured Ospreys team-mate Alun-Wyn Jones.

Jonathan Thomas, who suffered a blow to the head in a tackle by Jonny Wilkinson, has been cleared to start at blindside flanker.

Gloucester back-row Gareth Delve takes Popham's place on a bench which also features Cardiff lock Deniol Jones, who was called into the squad yesterday following Alun-Wyn Jones' withdrawal, and fit-again scrum-half Dwayne Peel.

For Roberts, who stands 6ft 4in tall and weighs just under 17 stone, it has been a rapid rise from full-time medical student, part-time rugby player to a Wales international in less than a season.

"It is crazy to think that last year I was down the pub with the boys to watch the Wales games - and I will be involved on Saturday," said Roberts.

"Last weekend was special for the whole nation. I was carrying the water and I had a tear in my eye as I looked around the stadium and dreamed I could be part of the Wales team.

"I didn't realise that dream would start now. It is going to be pretty special. I just hope to put a good performance in."

Roberts has been in the Blues squad for less than a season, largely playing at full-back, but his power and running skills quickly caught Gatland's eye.

"I have been impressed by his form with the Blues, he is a big physical man and he has a good kicking game," said Gatland.

"You can play as lightly different game with someone like Jamie. His ball-carrying has impressed me, he has run nice lines and he is strong in contact."

Roberts is in the third year of a medical degree but has taken the next eight weeks off. He will sit his exams in the summer with plans to complete the remaining two years on a part-time basis.

"It is rugby all the way for the next eight weeks - and then I will be cramming in the revision," he said.