The immediate impact made by the likes of Luis Diaz at Liverpool and Christian Eriksen at Brentford is obvious to see, but there are plenty of signings that more subtly made a big difference at their clubs.
There are times when it can be cheaper, less high-profile additions that have a huge influence in turning their side’s fortunes around, which is something to consider when there’s a clamour to go out and sign the biggest superstars around.
Here are six of our picks for unheralded signings that played a major role in bringing silverware to their clubs.
Petr Cech
You’d be hard-pressed to find a Chelsea fan with a bad word to say about Cech, given how good he was at his peak and the role he played in the most successful period of the club’s history, but it’s easy to forget quite how colossal the impact he made was.
Roman Abramovich had already spent over £150million on squad additions in the summer of 2003, with the likes of Damien Duff, Joe Cole, Claude Makelele and Scott Parker joining a squad that already boasted Frank Lampard and John Terry.
With all of those players, Claudio Ranieri’s Blues finished 11 points behind Arsenal’s Invincibles in 2004. Nobody was surprised when Ranieri was sacked.
The following season, with Cech replacing Carlo Cudicini between the sticks, Chelsea won the title and finished 12 points ahead of the Gunners, conceding just 15 goals – half as many as the season before – with Cech keeping 24 clean sheets from 35 starts.
The arrival of the Special One justifiably dominates the narrative, but he might not have quite that special without arguably the best keeper in the world at the time.
An absolute steal at £11million from Rennes.
Michael Carrick
Amid the arrival of Mourinho Cech at Chelsea, Manchester United endured the most fallow period of Sir Alex Ferguson’s tenure in the Premier League era.
Between 2003 and 2006 they didn’t make it past the Champions League round of 16 and finished 15, 15 and eight…