Djokovic celebrates 'big win' on return to Basel

This was Djokovic's 20th tour-level win of the year. It is the 21st consecutive season of his astonishing career in which he has achieved that tally.

After conceding the first set, Djokovic hung on against the 38th-ranked Humbert as he twice saved break points to escape an immediate setback in the second.

But the Serb, contesting his first indoor event since winning the Athens title last November, was solid from there, breaking Humbert's serve for the first time in the following game to kickstart his fightback.

Djokovic entered the tournament 319 points behind Spain's Rafael Jodar, who currently occupies the final ATP Finals qualification spot and also gained 50 points after coming through his first-round match.