The Belarusian was too strong for Latvia's Ostapenko, winning 6-4, 6-4 to book a last-16 tie against fellow four-time Grand Slam champion Naomi Osaka on Sunday.
Sabalenka will be bidding to reach a 15th consecutive Grand Slam quarter-final, but former world number one Osaka has impressed so far in reaching the fourth round at the All England Club for the first time.
"Another aggressive player. Another very powerful match. I'm ready to fight and do whatever it takes to get through," Sabalenka said of facing Osaka, against whom she holds a 3-1 winning record.
Sabalenka has lost in the semi-finals on each of her past three visits to Wimbledon.
The 28-year-old met Osaka at the same stage at the French Open last month, winning in straight sets only to then suffer a surprise loss to Diana Shnaider in the quarter-finals.
Former Roland Garros champion Ostapenko put up some resistance in the second set, but never seriously threatened Sabalenka.
Wimbledon 2026
Wimbledon took place from June 29th to July 12th at the All England Club in south-west London. It is the third of the four Grand Slams in the tennis season, and the only one played on grass.
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