After the despair from successive defeats at Everton and Manchester City it looked like a draw was all Arsenal were going to manage.
West Brom lived up to their reputation for dogged resilience and their goalie ,Ben Foster, had the game of his life.
Sanchez,for all his skill and guile,could not get the ball past him.
So Olivier Giroud’s late header from an inch-perfect cross from Mesut Özil has breathed life into Arsenal’s flagging title challenge.
Now they have to keep winning – all their games till the end of January against Crystal Palace, Bournemouth, Swansea City, Burnley and Watford.
And hope that Chelsea lose a few for a change.
Highlights…