Pulis admits the situation is far from ideal, but is confident Shawcross will be ready for the resumption of domestic action.
"You can't do anything about it now and I've got no worries about Ryan ahead of Saturday," Pulis told The Sentinel.
"We're training in the afternoon rather than the morning, so that gives him a bit of extra time.
"In the old days they used to play internationals on the Wednesday anyway, so it's nothing new really.
"And with Saturday in mind, I suppose you could look at it we've got one player out there and United have got four."