Greater Western Sydney have flown an umpire in from Melbourne to take Shane Mumford through the reasons why he is the AFL's most penalised player ahead of a potentially match-defining ruck battle with Brodie Grundy.

No player has given away more free kicks this season than Mumford, who was pinged eight times against the Brisbane Lions to bring his total to 72. That's 24 more than the next worst offender, which happens to be Grundy - his direct opponent in Saturday's preliminary final against Collingwood.

Shane Mumford has given away more free kicks than he's had actual kicks himself across his last three AFL seasons. Credit:Wolter Peeters

In fact, Mumford has conceded more free kicks than actual kicks he's had himself, as he did during the 2016 and 2017 seasons for the Giants prior to his short-lived retirement.

It's a startling statistic but one that Mumford admits needs to be dealt with urgently if GWS are to be any chance of progressing to a maiden grand final.