Premiership clubs splashed out over £150 million in the winter market.
Half of this record figure was recycled within the Premier League, but there was still a £75m net spend by top flight clubs, most of this disappearing overseas with some trickling into the Football League.
Mascherano is expected to sign the deal next week, but is not bound by the transfer window rules because he was already registered at Liverpool for the rest of the season.
So Nicolas Anelka at £15m is officially the most expensive signing in January window history.
The obvious reason for the record spending is the new TV rights deal, with an extra £300m for Premier League clubs this season.
The latest instalment of this bonanza landed in the clubs' bank accounts in January, the month Juande Ramos claimed was for desperate buyers before paying £21m for four players.