The brother and assistant of Southampton manager Ronald Koeman has said that an Achilles injury could see him miss Sunday's Premier League opener at Newcastle United.

The 52-year-old suffered the injury on the eve of their 2-0 Europa League win away to Vitesse tonight, which saw him enter the stadium on crutches.

His brother Erwin, who deputised for his sibling and took the post-match responsibilities, told reporters that the Dutchman may now miss the trip to St James' Park as a result of the training-ground accident.

"He knows he has already some problems with his Achilles and if you are involved in a training session then [things] can happen like what happened," he said.

"Okay, we will hear tomorrow what happened and we will hear tomorrow if he is on Sunday on the bench or not.

"Tomorrow morning he goes to hospital and then they will decide what to do."

Tonight's victory saw the Saints advance into the playoff stages of Europe's secondary competition, with the draw scheduled to take place tomorrow.