Dutch player Kiki Bertens has reached the fourth round of Roland Garros before. Now ranked #110 in the world, she managed to get a win over Mirjana Lucic-Baroni of Croatia, currently ranked #48 in the world, 36 64 62.
She gave Serena Williams (#1) a bit of a scare in the first set of their second round match but failed to get through 76(5) 63.
This is her second time in the second round of the US Open, her first was in 2012. This is also her fourth time in the second round or deeper in all the grand slams.