Mertens, who made her only deeper Slam run into last year's Australian Open semi-finals, will play Wednesday for a berth in Thursday's semi-finals against the winner of a later match between 116th-ranked US qualifier Taylor Townsend and 19-year-old Canadian 15th seed Bianca Andreescu.
Belgium's Mertens reaches quarter-finals at US Open
Highlights Elise Mertens
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