Crows midfielder David Mackay will be sidelined for up to a month with a hamstring strain.

Mackay, 27, sustained the injury during Adelaide’s loss to the Western Bulldogs on the weekend.

General Manager of High Performance Brett Burton said scans had revealed the extent of the injury.

“David experienced hamstring soreness in the second half of Saturday night’s match and sat out the last quarter,” Burton said.

“Unfortunately, further assessment has revealed a hamstring strain that will keep him sidelined for 3–4 weeks.”

Mackay has played all seven games this season, averaging 18 possessions and four inside 50ms. He celebrated his 150th AFL game against Fremantle in Round Six.

Mackay’s injury means the Crows will need to make at least one change to their team to play Geelong at Adelaide Oval on Friday night. 

The Club's next four games are against the Cats, Gold Coast, Greater Western Sydney and St Kilda.

See Adelaide's full injury update ahead of Round Eight