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The January window provides managers with an opportunity to reshuffle their squad ahead of the second half of the season.
Whether you've been sucked into a relegation battle, fallen off the title pace or trying to bat away challengers at the league summit, a shot in the arm in the form of a new arrival is always helpful in January.
Chelsea manager Jose Mourinho has assured fans that he did his business in the summer and said last month he hopes to 'start and finish' the season with the same squad.
And those comments go some way to explaining why the Blues boss is only the eighth keenest spender in terms of average net spend (fees spent minus fees received) in the January window.
But that doesn't mean the Portuguese manager is afarid to pull our the cheque book. Last season, Mourinho shelled out £43,500,000 on Nemanja Matic, Mohamed Salah and Kurt Zouma, but recuperated much of that expenditure with the £37,100,000 sale of Juan Mata to Manchester United.
Brendan Rodgers - during spells at Swansea and Liverpool - has been less keen to balance the books, however, and spends an average of £7.6million more than he makes back in sales during the January window.
The Reds manager leads the way alongside Stoke boss Mark Hughes, with Harry Redknapp spending a close third (£7.5m) after spells at Portsmouth, Southampton, Tottenham and QPR since the winter window was introduced in 2002/2003.
Arsenal manager Arsene Wenger features surprisingly high up despite the misconception that the Frenchman has tight purse-strings. Indeed, big-money moves for Theo Walcott (£9.1m), Alex Oxlade-Chamberlain (£12m), Emmanuel Adebayor (£7m) and Jose Reyes (£13m) have all gone through in January.
Meanwhile, Crystal Palace and West Ham bosses Alan Pardew and Sam Allardyce tend to earn more money in sales than they spend on new players, though Pardew's is a reflection of his time at other clubs.
Louis van Gaal, Ronald Koeman, Garry Monk, Nigel Pearson and Sean Dyche are all entering their first January window as Premier League managers, while Newcastle continue their search for a new boss.
Research provided by sports book Bwin. For more information follow this link.
Find out where your manager features in the infographic below:
