ESSENDON has received a significant blow ahead of its make-or-break clash with Hawthorn next weekend with forward Alwyn Davey expected to miss the next two to four weeks of football after MRI scans on Monday revealed damage to his AC joint.

Essendon football operations manager Paul Hamilton said while the scan results confirmed a grade three injury to Davey’s shoulder, the club was seeking further advice from a shoulder specialist.

“The results confirmed that Alwyn has a grade three injury to his shoulder which is fairly severe,” Hamilton said.

“There is very little he can do other than rest over the first couple of days. He is very sore and can’t lift his arm up at this stage so we will give him a period of rest.

“Once it is rested up and the swelling has gone down, we will start working on some basic movement patterns and build it up from there.”

Davey has played 20 games this year and kicked 14 goals, and is one of Essendon's best defensive forwards, laying 87 tackles for the year, third most at the club.

“We are disappointed that Alwyn is not going to be available because he is a very valuable player for us,” Hamilton said.

“He is a speedy small forward that gives you a little bit of bite around the packs and applies some terrific defensive pressure.”