England head coach Stuart Lancaster has revealed that Billy Vunipola is not guaranteed a starting place despite his spontaneous hat-trick against the CONSUR XV on Sunday.
The 20-year-old scored three times in six minutes as the Red Rose marched to a 41-21 victory in Montevideo at the weekend.
Despite his display, Lancaster insists that nobody is certain of a place in the starting lineup on their South American tour.
"He had a good game in terms of try-scoring," Lancaster told Sky Sports News. "I need to look at his contribution and those of all the others in back row because there are lots of decisions to be made.
"The breakdown was fiercely contested and at times we didn't deliver as good ball as we had wanted. I have some decisions to make as to how we go about the game. In terms of preparation it has been ideal. They were difficult opposition and we struggled in the first quarter and the last quarter to get the continuity we wanted.
"We were pleased to be 31-7 ahead at half time after a slow start. In the second half our set-piece ball dried up a bit. The most important thing for me [from this game] is that it is now crystal clear exactly how difficult it will be next Saturday."
Ben Foden scored two tries, while Tom Wood and Paul Doran-Jones also crossed the line.