The full-back arrived at Stamford Bridge in last summer’s transfer window and he played a key role in helping Chelsea win the Premier League title in Antonio Conte’s first campaign at the club.
Alonso has been a regular fixture in the first team at Chelsea this season, scoring two goals in seven Premier League games so far this term.
And Liverpool legend Carragher has been extremely impressed by the impact Alonso has had at Stamford Bridge since his arrival at the club.
Speaking to the Daily Telegraph, Carragher said: “I think he has been outstanding in the 12 months he has been here.
“He has a superb defensive record with Chelsea and he scores goals.”
Alonso will be hoping to feature for Chelsea when the Blues return to Premier League action after the international break on Saturday with a trip to Crystal Palace.
The west London side are aiming to get back to winning ways in the Premier League after the disappointment of their 1-0 loss to Manchester City before the international break.
Chelsea are currently fourth in the table and six points behind leaders Manchester City after seven games of the new campaign.
The Blues have kicked off their Champions League campaign in style, beating Qarabag and Atletico Madrid in their first two games.
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