REMEMBER Pierluigi Casiraghi, the Italian international signed by Chelsea in May 1998 for £ 5.4 million? Not many people do, for his 10 Premier League appearances cost around half a million a piece. Luckless Casiraghi sustained a bad injury in November of that year and was never seen again. Historically, big price tags haven’t weighed too well on the shoulders of some of Chelsea’s big captures. This summer, they’ve bought a clutch of major signings, all young – with the exception of old hand Thiago Silva from Paris Saint-Germain – and the one they’re still waiting for, Bayer Leverkusen’s Kai Havertz, could arrive at Stamford Bridge with an anvil-sized fee of £ 90 million hanging over him. History You can trawl through Chelsea’s back…