4. Ravindra Jadeja

Jaddu started his glittering career by winning the 2008 U19 World Cup. That same year he got picked by Rajasthan Royals in the IPL. Jaddu’s impressive performance helped RR win the maiden IPL season title.
Such was his performance that Aussie spin legend Shane Warne termed Jadeja as the ‘Rockstar’. Jadeja played another year for RR and then got banned for a year. The reason was that he approached other teams for higher pay and thus violated the player’s guidelines.
In 2011, Jadeja got picked for Kochi Tusker Kerala. After one season, the franchise got terminated permanently. In 2012 auction pool, CSK spent their entire purse on Jadeja. They won the tie-breaking bid against Deccan Chargers and purchased Jaddu.
Since then the left-arm spinner have played 102 games for CSK and has taken 81 wickets. He is currently the third highest wicket-taker for CSK. With the bat, Jadeja has scored 865 runs at a good strike-rate. Along with that Jadeja’s remarkable ability on the field makes him one of the best signings of CSK.
5. Faf du Plessis

It was during the 2011 auction when Faf de Plessis was purchased. However he didn’t get a single game but CSK won their second title that season. It was during the 2012 season that du Plessis made his IPL debut.
Since then the current South African skipper has been CSK’s regular member in the playing XI. He might be one of the underrated players but he had a huge impact on CSK’s successes.
So far he has played 63 games and has scored 1639 runs. He is currently the fifth highest scorer of CSK and has been a better batsman in the last couple of seasons. Thus we can safely say that Faf du Plessis is also one of the best signings of CSK.