Paris, Nov 1 (IANS): Russian Roman Safiullin earned the biggest win of his career year by stunning No.2 Carlos Alcaraz in the Paris Masters.

The qualifier recovered an early break in both sets of a shock 6-3, 6-4 victory, dealing Alcaraz his first opening-round loss of 2023.

Safiullin is up to No. 39 in the ATP Live Rankings with the victory, setting himself up to break into the Top 40 for the first time. The 26-year-old's upset win against Alcaraz follows breakthrough runs to the Wimbledon quarter-finals and the Chengdu final in recent months.

"Since qualies, I was not playing at this level but against Carlos and these Top 10, Top 20 guys, you have to lift up the level. I managed to do it,” said Safiullin in the post-match.

"For Carlos, it was not his best performance, but still I'm happy that I can win even if he's not in the best shape it's tough to beat him. So I'm really happy that I made it."

Alcaraz, who was forced to pull out of Basel due to problems with his left foot and lower back, was competing for the first time since his defeat to Grigor Dimitrov in September ending in the Shanghai last 16.

The defeat deals a heavy blow to his bid to finish the season atop the Pepperstone ATP Rankings for the second straight year; he remains 500 points behind world No. 1 Novak Djokovic in the ATP Live Race To Turin, with the Serbian set to open his Paris campaign on Wednesday.

Following a first-round bye in Paris, Alcaraz started brightly in both sets but was pegged back by the steadier play of Safiullin. The qualifier was aided by 27 unforced error count from the Spaniard, though he played his part in Alcaraz's miscues by defending well in the corners, particularly at the critical moments.

Playing in a nondescript white shirt devoid of any sponsor patches, the workmanlike Safiullin converted four of eight break chances in the match — two in each set — while saving two of four break points against Alcaraz, one of tennis' biggest superstars.

He improved to 3-6 against the Top 10 with the victory, backing up his win against Alexander Zverev in Shanghai. Safiullin has now reached the third round at four of the past five ATP Masters 1000s (also Madrid, Rome, Shanghai).

"Everything against these guys (is important). Tactical, physical, the mental part is very important," Safiullin said of his success against the ATP Tour's best. "(It's key) to stay focussed from the beginning to the end. Who can make it longer is going to be the winner," concluded Safiullin.

Alcaraz had not lost his opening match at a Masters 1000 since a three-set defeat to Tommy Paul last year in Montreal. The Spaniard had won nine openers in a row at that prestigious level prior to his Tuesday defeat.