World No 1 Jannik Sinner came back from a set down to take a gutsy 6-7 (3-7) 6-4 6-2 win against Tomas Martin Etcheverry at the Shanghai Masters.

A night after winning his 250th career match with a straight-sets victory, the 23-year-old Italian faced a much sterner third-round examination against the Argentine under the roof inside Qizhong Forest Sports City Arena that hosted play due to rain.

Sinner will next play American Ben Shelton, who beat him last year in Shanghai, or Spain's Roberto Carballes Baena on Tuesday.

"It was a very tough match, physically and mentally, so I am very happy to get through this one," said Sinner.

"I felt like it was a tough set that I lost. I had my chances [to win the first set], but these things can happen.

"Sometimes you have to wait for your chances, which I have done, trying to stay calm mentally, and that was the key."

Etcheverry produced the shot of the night with a stunning drop volley to bring up set point in the first-set tie-break, which he converted to take the lead.

Sinner began to better find his range in the second and, after trading breaks midway through the set, the Italian found another opportunity to level the match.

The momentum was all with Sinner in the third as he broke Etcheverry twice more to advance in two hours and 39 minutes.

Daniil Medvedev also came from behind for a 5-7 6-4 6-4 victory against Matteo Arnaldi to book his fourth-round berth against either Stefanos Tsitsipas or Alexandre Muller.

Medvedev was forced to dig deep to level the match after the Italian took a tight first set.

In the deciding set, Medvedev's experience and composure came to the fore as he clinched a vital break in the ninth game and held firm to close out the match in two hours and 44 minutes.

Carlos Alcaraz earned his spot in the fourth round with a 7-6 (7-5) 6-3 win over wild card Wu Yibing.

The world No 2, who remains unbeaten since his surprise second-round exit at the US Open, will play Gael Monfils or Ugo Humbert for a spot in the last eight.

• Shanghai Masters - ATP 1000 (October 2-13)
• Wuhan Open - WTA 1000 (October 6-12)
• Almaty Open, Kazakhstan - ATP 250 (October 14-20)
• Stockholm Open, Sweden - ATP 250 (October 14-20)
• European Open, Antwerp - ATP 250 (October 14-20)
• Japan Open, Osaka - WTA 250 (October 14-20)
• Ningbo Open, China - WTA 500 (October 14-20)
• Erste Bank Open, Vienna - ATP 500 (October 21-27)
• Swiss Indoors, Basel - ATP 500 (October 21-27)
• Guangzhou Open, China - WTA 250 (October 21-27)
• Toray Pan Pacific Open Tennis, Tokyo - WTA 500 (October 21-27)

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