The first ATP 500 event of the season took place in Rotterdam, with a solid field of players fighting for the title. Daniil Medvedev and Stefanos Tsitsipas were the top seeds, and they both failed to reach the quarters, leaving the door opened for their rivals to battle for the crown and 500 points.
Following the Montpellier final, Vasek Pospisil kept that form in Rotterdam and toppled the top seed Daniil Medvedev 6-4, 6-3 in 67 minutes for his seventh top-10 victory in a career and the second in the last couple of days.
Vasek won ten points more than Daniil, fending off five out of six break chances and stealing the Russian's serve three times to control the pace and bring the encounter home in no time. Pospisil finished the match with 21 winners and 13 unforced errors, leaving Daniil on a 21-19 ratio that wasn't enough to keep him safe or earn at least a set.
It was a promising start for the US Open finalist, breaking Vasek in the first game and holding at love with a perfect drop shot for a 2-0 advantage. The scoreboard changed in the fourth game when Medvedev hit a double fault, bringing Pospisil back to the scoreboard's positive side before creating an excellent chance on the return at 4-4.
Staying focused, Vasek fended off three break chances with booming serves, bringing the game home after forcing Daniil's error and stealing the rival's serve a few minutes later for 6-4 in 37 minutes.
Stefanos Tsitsipas and Daniil Medvedev suffered early losses in Rotterdam.
With momentum on his side, Vasek sailed through his service games in set number two, keeping the pressure on the other side of the net and breaking Daniil at 2-1 when the Russian netted an easy volley.
Pospisil confirmed the break with a hold at 15 and delivered another comfortable hold at 5-3 to advance into the second round and score one of his most notable wins ever. Stefanos Tsitsipas kicked off the campaign with a 6-7, 6-3, 6-1 victory over Hubert Hurkacz, playing well in sets two and three and hoping for more in the second round against Aljaz Bedene.
Instead of that, the Slovenian defeated the Greek 7-5, 6-4 in an hour and 32 minutes. The Slovenian grabbed four points more than the second seed, repelling all five break chances to keep the pressure on the other side of the net.
Struggling to find his strokes, Stefanos hit 12 winners and 18 unforced errors, making too many errors with his forehand and losing ground in the opener's closing stages and opening games of set number two.