When Warren Gatland bumped into Wales Rugby Union chief executive Martyn Phillips on Friday, the coach predicted Wales would beat Scotland by 20 points.

Gatland said Phillips was shocked.

The rest of the rugby world was, too, when Gatland’s side whipped Scotland by 27 points, 34-7, to open the Six Nations.

Wales were underdogs but, to make up for eight British Lions out injured, Gatland picked 12 Scarlets and started 10.

Almost 10 years to the day after he started 13 Ospreys in his first match as Wales coach and beat England at Twickenham, Gatland’s gamble on the Scarlets paid off.

Their self-belief, attacking attitude, and understanding made up for more than 500 caps’ worth of talent being unavailable.

“It was an afternoon I was expecting with the way we have trained the last couple of weeks,” Gatland said.

“There was definitely a quiet confidence in the squad, they have been outstanding in their preparation, and we went into the game expecting to win reasonably comfortably.”

Wales scored four tries, bombed at least three more, and kept Scotland scoreless until the 78th minute when Peter Horne crossed for a consolation try.

Experienced Wales fullback Leigh Halfpenny scored two tries and added 14 points with the boot for a personal tally of 24.

“Apart from the soft try at the end our defence was outstanding,” Gatland said.

“Getting the bonus point was pleasing as well.”

Wales will be the underdogs again next week at Twickenham when they face the two-time defending champions but Gatland expects to have at least two of his Lions backs available.

Liam Williams will take a full part in training on Monday after an abdominal problem, and George North should be available after tight hamstrings.

“I’ve said the draw was great for us. We’ve got England and Ireland away (in the next two rounds),” he said.

“We’ve often had pretty tough opening encounters so getting Scotland at home first up for us was a great opportunity.

“There were a lot of players who were involved last year (in the loss at Murrayfield) and they wanted to make up for that disappointment.

“Next week, we go to a venue where we’ve had a lot of success in the last 10 years.”

Gatland wasn’t ready to predict the result for next week’s game yet.

Scotland host France in their next outing on February 11.