Observers of the US economy will be familiar with the so-called 'Tiger effect' – the recurrent phenomenon that when Tiger Woods, the world's leading golfer, wins a tournament, business confidence surges and productivity goes up.

Now The Diary has discovered a strange new phenomenon sweeping the City – the 'McGrath effect' – whereby the productivity of UK law firms rises proportionately with each crushing defeat inflicted on the England cricket team by Ashes rivals Australia.

Judging by the number of UK partners apparently struck down by sudden illness or mysteriously detained in unscheduled meetings during the first two days of the opening Test, managing partners keeping an eye on the bottom line – rather than the boundary rope – will be hoping for further swift and bloody reverses for Vaughan & Co over the coming weeks.