FRANK LAMPARD has issued an injury update on Nathan Patterson after the full-back missed Sunday's Premier League clash against West Ham.

The former Rangers youngster moved to Goodison Park in January, but has struggled to make an impact as Everton battle it out to avoid relegation.

Lampard insisted after Sunday's game that he had planned to utilise Patterson against West Ham, but that changed after he rolled his ankle in training.

Updating on the injury today, Lampard said: "In terms of injuries, Nathan Patterson will be out for a certain period of time.

"He has been down to see a specialist on his ankle and we are looking at having a small operation later this week.

"He will be out."

Patterson had played for Scotland on international duty against both Poland and Austria but is yet to play for Everton in the Premier League.

His injury comes as fellow Scotland teammate Kieran Tierney faces a lengthy spell out.

The former Celtic man is set for a scan on Tuesday that will determine the extent of a worrying knee injury.

On Tierney, Arsenal manager Mikel Arteta said: “He is seeing the specialist tomorrow and we will know more about the extent of the injury but the feeling that he had wasn’t really positive and what the scan showed either. We have to wait and see what happens.”