Morgan Williams hung up his boots after captaining Canada at Rugby World Cup 2007 and has since been appointed their national skills coach, but he will be back in action at the USA Sevens as one of three changes forced on coach Shane Thompson as a result of injuries or other commitments.

Williams, who turns 32 in April, last played Sevens for Canada at the 2006 Commonwealth Games but is no stranger to the IRB Sevens World Series and his experience was a key element in the decision to coax him out of retirement to join Nathan Hirayama and Rob Turk as additions to the squad that lost to the USA in the Shield semi-finals in Wellington.

"There were a lot of factors, including the various players' school commitments, availability to travel, but more importantly we needed someone with experience, who had worked with the players and worked out with the players as well, and with all that in mind the decision was reached to coax Morgan off the retirement couch and back on the field," said Geraint John, Rugby Canada's High Performance Director.

Turk and Hirayama were both unable to travel to Wellington, but return to the Canada squad after Ben Grant suffered a fractured fibula against Samoa and Sean-Michael Stephen's back injury did not respond to treatment. The other player to miss out is Harry Jones, who links up with Canada's Under 20 team ahead of their Freedom Cup meeting with the USA in Florida on 15-16 February.

"I am pretty comfortable with the decision," admitted Williams. "I have been training a lot with the various squads, so fitness is fine, and as a skills coach I have probably been doing more passing and catching with all the age grades, so I am feeling pretty sharp. I feel really good, so this will be a good fit."

The final squads of the 16 teams participating in the USA Sevens at PETCO Park this weekend are yet to be announced, although Australia have also had to make a change with Henari Veratau drafted in from the Queensland Reds to replace the injured Luke Inman as they look to build on their Cup semi-final in Wellington.