Novak Djokovic celebrated his elevation to world number one by reaching a new personal landmark to reach the Paris Masters quarter-finals on Thursday after beating Bosnia’s Damir Dzumhur in his last 16 tie, after the Bosnian was forced to retire trailing 6-1, 2-1.

Djokovic who is the second seed has now extended his sequence of consecutive winning sets to 30, passing his previous best mark of 29 from 2015.

The four-time Paris champion faces Marin Cilic in the last eight on Friday. He takes over as world number one in the latest ATP rankings published on Monday from Rafael Nadal, who withdrew injured from Paris on Wednesday.

Cilic, the fifth seed, secured his quarter-final ticket with a 7-6 (7/5), 6-4 defeat of Grigor Dimitrov after firing 29 winners to advance to the last eight in the Paris Masters for the third straight year. The win improved the Croat’s prospects of making the ATP Finals in London which begins on November 11.