Table: tennis_rivalry
Columns: year
tournament
surface
round
winner
score
length_h_mm
sets
federer
nadal

Question: What tournament did Nadal win and had a nadal of 16?
SQL: SELECT "tournament" FROM tennis_rivalry WHERE "winner" = 'nadal' AND "nadal" = 16

Question: What was the nadal in Miami in the final round?
SQL: SELECT MAX("nadal") FROM tennis_rivalry WHERE "round" = 'final' AND "tournament" = 'miami'

Question: What were the sets when Federer had 6 and a nadal of 13?
SQL: SELECT "sets" FROM tennis_rivalry WHERE "nadal" = 13 AND "federer" = 6