Round four of the Sinquefield Cup produced exactly one decisive result, but it was a spectacular one. Round four of the Sinquefield Cup produced exactly one decisive result, but it was a spectacular one. Praggnanandhaa beat Jorden van Foreest with a queen sacrifice that turned a quiet opening into a rout, while Wesley So preserved his tournament lead with a draw against Levon Aronian in the day's marquee pairing.\n\nPragg's sacrifice\n\nPraggnanandhaa offered a pawn sacrifice as early as move 8 against Van Foreest, later admitting he was surprised when it got taken: "this was like one of 10 things I looked at." Van Foreest's 10...Bc6 retreat, which cost him an 11-minute think, opened the door to chaos, and Black soon sacrificed his queen outright. Pragg wrapped up a queen-versus-rook endg