Casper Ruud and Stefanos Tsitsipas crash out of US Open

But Novak Djokovic is safely into the third round

Casper Ruud is out of the US Open (Charles Krupa/AP)

Novak Djokovic is safely into the third round, but there were a couple of big shocks on day three of the US Open.

Seventh seed Stefanos Tsitsipas was knocked out in five sets by Dominic Stricker, a qualifier ranked 128 in the world.