Defending champions Carlos Alcaraz and Aryna Sabalenka march on at Madrid Open

Alcaraz is aiming to become the first man ever to win three straight titles in the Spanish capital.

He came into the tournament nursing an arm injury that delayed the start of his European clay-court campaign but he was impressive in a 6-3 6-3 win over Brazilian Thiago Seyboth Wild.

Alcaraz said: "I think I played at a really good level. Coming into this match I was nervous a little bit because I didn™t know how my forearm was going to be. Thiago has big shots. He is really strong. I am really happy with the performance."

Next the second seed faces a rematch of last year™s final against in-form German Jan-Lennard Struff, who beat Ugo Humbert 7-5 6-4.

Seventh seed Andrey Rublev claimed a much-needed 7-6 (10) 6-4 win over Alejandro Davidovich Fokina and Hubert Hurkacz continued his good form to reach round four but Holger Rune was beaten 6-4 4-6 6-3 by Tallon Griekspoor.

Sabalenka has struggled for form since winning her second successive Australian Open title and was given a real test by American teenager Robin Montgomery.

The second seed raced through the first set but 19-year-old Montgomery, who defeated Katie Boulter in the second round, found her range in the second set and began to trouble Sabalenka.

Montgomery won the set on a tie-break to force a decider but ultimately Sabalenka edged a 6-1 6-7 (5) 6-4 victory.

Fourth seed Elena Rybakina eased to a 6-1 6-4 win over Mayar Sherif while teenager Mirra Andreeva is again making waves in Madrid.

The Russian, who turns 17 on Monday, reached the fourth round for the second year in a row with one of the biggest wins of her career, taking out Wimbledon champion Marketa Vondrousova 7-5 6-1.

Andreeva next meets 12th seed Jasmine Paolini, who defeated Caroline Garcia 6-3 6-2, while 18-year-old Czech Sara Bejlek is also through to the last 16.

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