Britain's Andy Murray kept up his hopes of dethroning Novak Djokovic as world No1 later this week by progressing with greater ease than the Serb at the Paris Masters.
Murray, who is on a 17-match unbeaten run, reeled off eight games in a row as he beat Frenchman Lucas Pouille 6-3, 6-0.
The Scot, 29, can hit the summit of the rankings for the first time in his career if he wins the Paris title for the first time and Djokovic fails to reach Sunday's final.
He could even unseat the 12-time grand slam champion just by reaching the final – if Djokovic exits the tournament before the last four.
Djokovic was given a scare by Grigor Dimitrov before he progressed to the fourth round.
He lost the first set but responded in convincing style to beat the Bulgarian 4-6, 6-2, 6-3.
Murray said: "If Novak reaches the final, he keeps that spot. I just want to finish the year as best as I can. The goal wasn't to get to number one this year, but if it happens that's great."
Murray is enjoying his most successful season to date, having won seven titles this year including a second Wimbledon crown.
Djokovic also has seven tournament wins in 2016 but has looked out of sorts since the summer and has not lifted a trophy since July.