Friday's Hertogenbosch round of 16 pits Caty Mcnally against Solana Sierra on grass. Caty Mcnally comes in at 6 wins from the last ten. Solana Sierra brings a 4-match winning streak into this one, 8-2 across the last ten.

Solana Sierra has had the better of this rivalry, winning 1 of 1 against Caty Mcnally.

Caty Mcnally is clearly higher-rated on grass — our number puts Mcnally around 79%. Sierra needs several things to break right at once; the percentages say they usually don't.