Stoke City boss Mark Hughes says Victor Moses' injury is yet to be clarified.
Moses will be sent for more tests during the fortnight's international break after pulling up injured in the early stages of today's 3-1 defeat at Sunderland.
"Victor had a bit of tightness after the Newcastle game (on Monday)," Hughes stated.
"We had him scanned and nothing showed on the scan. He trained Thursday and Friday and looked good to go.
"But he felt discomfort and we weren't going to take a risk.
"We are hoping it's nothing serious, but given nothing showed on the scan we've got to get to the bottom of what's causing it."
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