ST KILDA wingman Jack Newnes is out for the rest of Saturday afternoon's game against Sydney at Etihad Stadium after suffering concussion in the first quarter.

Newnes, 24, copped a heavy knock to the head when he collided with Callum Mills after chasing a loose ball.

Jade Gresham kicked his side's second goal after the incident and Saints players congratulated Newnes, but the 100-gamer had to leave the field before the next centre bounce.

He went down to the rooms and had a concussion test but was not able to return.

St Kilda was left with two on the bench for a short period after Mav Weller hurt his right ankle, the same one he injured at training a little over a fortnight ago.

However, Weller returned to the field.