The Spanish full-back has been a regular fixture in the first team at Stamford Bridge since signing for the Blues from Fiorentina back in the summer of 2016.
Alonso helped Chelsea FC to win the Premier League title in his first campaign at the club under Antonio Conte and the full-back has been earning lots of praise for his solid displays in recent weeks.
The Spaniard helped to inspire Chelsea FC to their fourth straight win of the season under Maurizio Sarri as they claimed a 2-0 win over Bournemouth on Saturday afternoon.
And BBC Sport pundit Crooks feels that Alonso has never performed better in a Chelsea FC shirt.
Writing in his column for BBC Sport, Crooks said: “For the third consecutive week Alonso has made my team of the week.
“The Spain international is playing better than I have ever seen him play.”
Chelsea FC will look to maintain their 100 per cent start to the new season when they take on Cardiff City at Stamford Bridge after the international break.
The west London side are aiming to challenge for the title this season after they finished in fifth place and won the FA Cup under Antonio Conte last term.
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