USA captain Madison Hughes will miss this weekend's Cape Town Sevens leg of the World Series to take a brief hiatus from international rugby.
Anthony Wellmers, named as the 13th man in the squad prior to the opening round of the Series, will move into the side for the tournament.
"We have had to do the right thing by Madison considering the year of rugby he has had," head coach Mike Friday, who will also miss this weekend's competition at the Cape Town Stadium, told USA Rugby's website
"He has played every Sevens Series tournament the last 12 months and a lot of minutes in those tournaments.
"We felt it was important that Madison was in Dubai for the start of the season to lead the team, but the plan was always that he would not be exposed to more significant travel time and additional playing time as the risk of injury is too high."
Hughes will start a three-week recovery period upon his return to the USA and will have a further five-week conditioning block leading into the Sydney and Wellington double-header of the Series beginning in late January.
In Hughes' absence, Perry Baker has been named captain under acting head coach Chris Brown.
USA squad for Cape Town Sevens: Perry Baker, Danny Barrett, Andrew Durutalo, Alec Gletzer, Martin Iosefo, Matai Leuta, Folau Niua, Don Pati, Stephen Tomasin, Maka Unufe, Anthony Welmers, Kevon Williams