Another player missing the trip is Yoann Folly. The future of both players is in doubt at Home Park.
Sturrock didn't say too much about Walton's situation.
He said: "I have said all along that there is a clean slate for everyone.
"Simon has asked to be a centre-half and taking that into consideration, I have other players."
It doesn't look good if Sturrock can dismiss the former Q.P.R. player becuase he has asked for a change of position. The clean slate maybe doesn't quite apply.
The opening game of the tour is at Skelmersdale tomorrow.