With the 2019 U.S. Open set to kick off Monday in New York (11 a.m. ET), SI's tennis experts and writers Jon Wertheim, Stanley Kay, Jamie Lisanti, and Kellen Becoats pick winners, discuss this year's top storylines, highlight must-watch matches and more.
What did you learn from the lead-up hardcourt events?
Jon Wertheim: We've learned that...Bianca Andreescu is for real...Daniil Medvedev is for real, at least in best-of-three matches...that Nick Kyrgios is still susceptible to visits from the Demi-gorgon...that Rafa Nadal can really play on hard courts...that Serena Williams is both dangerous and delicate.