Chelsea have been criticised for their transfer recruitment drive in recent years with many deals costing the club millions yet failing to make the right impact.

Before Enzo Maresca took over, the signings of Christopher Nkunku, Robert Sanchez, Raheem Sterling, Kalidou Koulibaly and Axel Disasi have all been questioned. Last summer, Joao Felix, Renato Veiga and Kiernan Dewsbury-Hall all joined with the first two already leaving on loan.

Despite the millions of pounds spent under Clearlake Capital's ownership, Chelsea still seem to have so much still to do to return to the pinnacle of football. With pressure mounting on Maresca, there is scope for the Blues to add to their squad with free agents.

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Here, we look at some of the club's best free transfers.

Thiago Silva

Under Frank Lampard, Chelsea completed the signing of Thiago Silva on a free after he left Paris Saint-Germain. He signed a one-year deal in 2020 and stayed at the club until 2024.

The Brazilian arrived after winning titles with AC Milan and PSG but had failed to win the Champions League. In his first season at Stamford Bridge, he lifted the prestigious competition.

Silva went on to play 155 times for the club and became the first defender to win Chelsea's Player of the Year in 2023 since John Terry did in 2006. He departed at the end of his contract last summer and returned to Fluminense.

Didier Drogba

Drogba is one of Chelsea's best-ever strikers. After signing from Marseille in 2004, Drogba won 10 trophies including the 2012 Champions League with his historic header and winning penalty.

After a short spell in China with Shanghai Shenhua, he moved to Galatasaray, helped them win the Super Lig title before returning to Stamford Bridge in 2014.

A one-year deal was signed and won his fourth Premier League title under Jose Mourinho.

Samuel Eto'o

Another iconic free striker transfer came with Samuel Eto'o in 2013. After being part of the small group of players which moved to Russian club Anzhi Makhachkala, the Cameroon international reunited with Mourinho on a one-year deal.

He arrived after Chelsea failed to land Wayne Rooney and came on the back of scoring over 250 goals for the likes of Barcelona, Inter Milan and Mallorca. He bagged 12 times for the Blues including a hat-trick against Man United.

Chelsea never got the best of Samuel Eto'o but nevertheless, his spell was an enjoyable one.

Michael Ballack

Following the expiry of his Bayern Munich contract, Ballack moved to Stamford Bridge after rejecting moves to Manchester United, Real Madrid, Inter Milan and AC Milan. He explained the decision to move to Chelsea was helped by Robert Huth and Jens Lehmann.

Having won three Bundesliga titles with Bayern, the midfielder joined to compete with Frank Lampard, Claude Makelele and Michael Essien as Mourinho's options in midfield.

Ballack spent four seasons in London, lifting three FA Cups, one Premier League and the EFL Cup, making over 160 appearances. He left in 2010 before retiring in 2012.