London - Mauricio Pochettino has urged Son Heung-Min to follow his superb goal against Chelsea with a sustained spell of excellence.

Son's brilliant solo strike fired Tottenham into a three-goal lead in Saturday's impressive 3-1 win over their London rivals at Wembley.

After Dele Alli and Harry Kane netted for Tottenham, the South Korea winger's 50th goal for the club ensured that Spurs ended Chelsea's unbeaten league start to the season.

Chelsea's defence were unable to cope with Son's speed and his influential display was welcomed by Tottenham boss Pochettino after the Korean's struggles earlier this term.

Having been at the World Cup with South Korea in the summer, Son returned to international duty with his country in August in a bid to earn exemption from military service by winning the Asian Games.

He achieved that feat but a gruelling schedule took its toll on the 26-year-old and he had been a shadow of his usual self in the wake of those international exertions.

Spurs' reward for allowing Son to go to the Asian Games was the promise he would not be called up for the most recent international break and Pochettino reckons that was a good bit of business.

"You can see on the pitch, Son's performance was fantastic and you can see he deserved it because the summer for him was very difficult," he said.

"In the last international break he was here, training hard. It is one of the reasons that he showed he is fresh, his physical condition is much better and I think it is going to help him for the rest of the season."

Son could have already had four goals by the time he finally beat Chelsea goalkeeper Kepa Arrizabalaga in the second half.

"It was fantastic, everyone that saw the game was in love with the action," Pochettino said.

"It was fantastic action, talent. It was a fantastic capacity to make what he made, it was an outstanding action for a very good player like him."