Flanker Joe Harley has joined the Scotland team touring South Africa as two other forwards headed home, officials said.
Loose forward Ryan Wilson dislocated his shoulder during a 30-17 loss to South Africa last Saturday in the second round of a four-nation tournament.
And lock Jim Hamilton, who was sin binned in that game, will miss a third-place play-off with Italy to be with his wife who is expecting their child.
Wilson is the fourth Scottish forward to suffer a tour-ending injury after flank forward and captain Kelly Brown, prop Geoff Cross and hooker Pat MacArthur.
Scotland face the Italians in Pretoria on Saturday in the first half of a Test double-header followed by the final between South Africa and Samoa.
Harley, 23, has fond memories of Italy, making his first start for Scotland against them in a 34-10 Six Nations victory at Murrayfield four months ago.
The Scots lost 27-17 to Samoa in Durban two weeks ago, but gave a much better display against the Springboks and held an 11-point lead in the second half.