Alonso has been in good form so far this season and he has been a regular fixture in the first team at Stamford Bridge since signing for the Blues from Fiorentina back in 2016.
The left-back played a key role in helping Chelsea FC to win the Premier League title in his first season at the west London club, and he has been in good form so far this term.
Alonso, like the rest of his team-mates, has been getting used to life under new manager Maurizio Sarri at Stamford Bridge this season.
And former Arsenal star Keown was hugely impressed by what he saw from Alonso during Chelsea FC’s victory over Bournemouth in the top flight this weekend.
Speaking on Match of the Day, Keown said: “Alonso is different class down the left.
“They changed their formation this year to adapt but no-one seems to have told him as he is flying own the left hand side even more than when he was a left wing-back.
“We know what he can do, he has scored lots of goals.
“He wants to stay high on the pitch and he’s been a real success for them.”
Chelsea FC have won all four of their opening Premier League games this season to leave them joint-top of the table.
The Blues will be aiming to challenge for the title this term, and they return to Premier League action when they take on Tottenham Hotspur at Wembley after the international break.
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