The Premier League champions endured a tough start to the 2017-18 season following a shock 3-2 loss to Sean Dyche’s Burnley side at Stamford Bridge.
Club captain Gary Cahill and Spanish midfielder Cesc Fabregas were both sent off during their Premier League opener.
Chelsea were forced to draft in Tiemoue Bakayoko for the trip to Tottenham despite the summer signing’s lack of preparation for his Premier League debut.
While the French midfielder impressed in last weekend’s 2-1 win, Alonso proved to be the key man for the defending top-flight champions.
The former Bolton Wanderers defender broke the deadlock in the first half with a superb free-kick before Alonso restored Chelsea’s lead with two minutes to go.
Ex-Arsenal defender Keown credited Chelsea boss Antonio Conte with providing an environment for the Spanish left-back to thrive in his Blues team.
“The key to their performance was Marcos Alonso. It is astonishing how Antonio Conte is getting these fantastic performances from him,” Keown told the Daily Mail.
“When Chelsea were losing against Burnley on the opening day, Alonso was the player who seemed most determined to drag his side back into the game.
“Alonso was their driving force again at Wembley — he takes it upon himself to push his team forwards. When Chelsea got that free-kick you could see David Luiz step aside for Alonso — he knew his team-mate could hit it.
“Last season he put in decent performances for Chelsea but now he is their matchwinner. On Sunday, Tottenham did not have a player who offered similar inspiration.”
Chelsea signed Alonso in a £17m deal from Serie A giants Fiorentina in the 2016 summer transfer window.
The Blues were a key part of the Chelsea team that won the Premier League title with two games to spare last term after finishing seven points ahead of Tottenham.
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