One of the less savoury parts of modern football is the way that it has become accepted that players try and get it each other sent off.

Whereas 20 years ago waving an imaginary card at the referee was thought lowest of the low, any attempt to gain an advantage now seems to be accepted as fair game.

To the extent that the world's best player Lionel Messi stooping to that level in Barcelona's 2-0 win at Arsenal on Tuesday passed virtually without comment.

But it makes you wonder why

players at all levels are clearly under instruction to try to unlevel the playing field, when their managers are so often keen to downplay the effect of playing a team a man down.

Neal Ardley alluded to the difficulties it poses after his AFC Wimbledon side had laboured to a 1-0 win Carlisle on Tuesday.

The visitors' goalkeeper Mark Gillespie was sent off and Wimbledon scored from the resulting free kick and yet they were left hanging on for a previous three points.

Of course it can also work the other way - Colchester were 2-0 up at Bury on Saturday when Tom Eastman got sent off and ended up losing 5-2.

But it seems red cards have become a bigger part of the game than they ever needed to become - especially when there probably less bad tackles and punch ups than ever before.

Gone are the days when you should feel disgraced at being sent off - as Kevin Keegan and Billy Bremner were in the 1974 Charity Shield.

The pendulum has gone too far the other way and the rulemakers and referees - not to mention players and managers - should do more to keep 22 players on the pitch.