World No 1 Jannik Sinner of Italy needed three sets to overcome Tallon Griekspoor of the Netherlands 6-7 (8), 6-3, 6-2 in the first round of the Terra Wortmann Open on Tuesday in Halle, Germany.

Sinner hit 15 aces to Griekspoor's 11 and saved all four break points he faced while going 3-for-4 on opportunities to break his opponent's serve.

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No 2 seed Alexander Zverev of Germany also had to rally to beat countryman Oscar Otte 6-7 (5), 6-3, 6-4. No 4 seed Andrey Rublev of Russia wasn't as fortunate, falling to Marcos Giron 6-4, 7-6 (5).

No 6 seed Stefanos Tsitsipas of Greece survived a pair of tiebreakers, saving a set point in the first set, to defeat German wild card Henri Squire 7-6 (7), 7-6 (2). No 7 seed Alexander Bublik of Kazakhstan, Christopher Eubanks, Arthur Fils of France and Australian qualifier James Duckworth also won in straight sets.

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Cinch Championships

No 1 seed Carlos Alcaraz of Spain advanced while three seeded players were shown the door in opening-round action in London.

Alcaraz won 13 of 15 net points while defeating Francisco Cerundolo of Argentina 6-1, 7-5. Italy's Lorenzo Musetti stunned Australian No 2 seed Alex de Minaur 1-6, 6-4, 6-2, finishing with a 7-0 edge in aces and saving 8 of 12 break points along the way.

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French qualifier Giovanni Mpetshi Perricard ousted No 6 Ben Shelton 6-3, 7-6 (3), and Italy's Matteo Arnaldi defeated No 8 Ugo Humbert of France 3-6, 6-1, 7-6 (6), saving a match point down 6-5 in the third-set tiebreaker before completing the upset.

In the draw as a wild card, Andy Murray of Great Britain fought past Australian qualifier Alexei Popyrin 6-3, 3-6, 6-3. Other winners Tuesday included No 4 seed Taylor Fritz, No 5 seed Tommy Paul, Sebastian Korda, Brandon Nakashima, Brits Jack Draper and Billy Harris and Chile's Alejandro Tabilo.