Chelsea spent £24m to sign Alonso from Fiorentina just before the summer transfer deadline. The Blues had signed expensive left-backs before - Baba Rahman for an initial £14m a year earlier, Filipe Luis for £13.5m the year before that. Neither impressed and they were on their way again within one season - Luis back to Atletico Madrid, Rahman to Schalke on loan. Rahman had made only 11 league starts for Chelsea, Luis just nine. At the time £24m seemed laughable but Alonso has since gone to prove everyone wrong. At Stamford Bridge on Monday night, he rifled home for Chelsea against Middlesbrough, to take them to the verge of the Premier League title. He may not be one of the Blues’ biggest names, but he has undoubtedly proved to be one of their most important this season.