"We don't think it's a major problem, we think he's just twisted it," Coppell explained.
"He tried to spin and his studs caught in the grass a little bit, but we don't anticipate any long-term problems with him.
"It was a shame because once again he had come on and looked very, very lively."
The 19-year-old, who recently committed himself to The Royals until 2009, netted twice against the Swedish minnows.
Long is in contention to face Orgryte on Tuesday evening along with James Harper and Graeme Murty.
The tour is over though for Brynjar Gunnarsson, he will fly home early for treatment to a groin injury.