A concerned Collingwood fan has written a letter to president Eddie McGuire expressing concerns over the club's injury crisis and pleading for an internal review.

The Pies could have as little as 26 players available for selection this week as the casualties continue to pile up in what has been an ongoing issue at the Holden Centre over the last few years.

Soft tissue issues have been the main source of their problems, with Taylor Adams (hamstring), Jordan De Goey (hamstring), Darcy Moore (hamstring) and Ben Reid (hamstring) the latest to go down.

Self-titled 'hardcore Pies fan' Shaun Campbell wrote to both McGuire and chief executive Mark Anderson and shared an image of his letter on Twitter on Tuesday.

Campbell said the key actions that should take place include identifying the root cause of the injuries, reviewing the soft cap and Holden Centre surface and being more transparent with fans.