There is a surprise call-up from outside Gatland’s 32-man autumn Test squad for Cardiff Blues prop John Yapp. Yapp packs down in the front row after Ospreys loosehead Duncan Jones was ruled out by a foot injury.

Yapp’s Blues colleague, wing Tom James, could also be summoned by Gatland if full-back Morgan Stoddart fails a fitness test.

Stoddart faces checks on an ankle injury tomorrow, and if he is ruled unfit, then Halfpenny will replace him at full-back with James starting on the wing.

Both James and Yapp have now officially been called into the Wales squad.

Centre Gavin Henson, meanwhile, was not considered for selection due to an ongoing Achilles problem.

Henson withdrew from the Springboks game less than 24 hours before kick-off, and Gatland is now awaiting reports from a specialist about the injury.

Captain Jones moves from blindside flanker to number eight instead of Andy Powell, who was man of the match against South Africa, with flanker positions taken by Dafydd Jones and Robin Sowden-Taylor.

It is all change in the front five, where there is a rare start for towering Newport Gwent Dragons lock Luke Charteris, while Scarlets wing Mark Jones returns following a knee injury.

Elsewhere, James Hook wears the number 10 shirt, with two uncapped players named on the bench in Sale Sharks prop Eifion Roberts and Ospreys fly-half Dan Biggar.

There is a full Test debut for Scarlets number nine Martin Roberts, with Sale’s Dwayne Peel among the replacements.

Gatland said: “We have a short turnaround before we face Canada, and this was always going to be a game in which we tried to utilise our squad.

“We have a chance to put defeat against South Africa behind us and really try to build some momentum before New Zealand and Australia come to town, so we know what we need to achieve against Canada.

“There are lots of changes from the weekend, but we have maintained consistency by keeping Ryan in there as captain, and we have some experience and impact players, too, on the bench.”