Elise Mertens and Yuliia Starodubtseva meet in the quarterfinal at Monterrey on Friday. Elise Mertens has dropped 2 straight and sits at 6-4 over the last ten. Yuliia Starodubtseva has won 4 of the last 10.

Hold strength tells the story — 63.4% versus 58.1% on first-serve points in Mertens's favor. The edge belongs to Mertens — real, but not the kind you take for granted at this level.