Austria's Dominic Thiem battled into the second round of the Rotterdam World Tennis on Wednesday after Alexander Zverev's challenge fizzled out in a racquet-smashing tantrum.
The German teenager lost 3-6, 6-3, 6-4 after dominating in the first set against second seed Thiem. He ended up smashing a racquet with five heavy blows in the final set after dropping serve.
The meltdown did not help in the end, with world number eight Thiem going through after one and three-quarter hours to next face France's Gilles Simon.
Grigor Dimitrov advanced with a 6-7 (4/7), 6-2, 6-4 win over Alexander's elder brother Mischa Zverev as the red-hot Bulgarian racked up his 15th win of 2017.
Dimitrov, who captured his second title of the season last weekend on home ground in Sofia, had to dig deep, however, to see off Zverev who stunned world number one Andy Murray at the Australian Open last month.
The 25-year-old Dimitrov improved to 15-1 on the season and will next face Denis Istomin, who beat Novak Djokovic in the second round in Melbourne at the season's opening Grand Slam.
Dimitrov, the fifth seed, took victory in just under two hours, firing his 11th ace for a match point and breaking on four of nine occasions.
"I'm pleased with the win. Mischa did not make it easy for me with his game. I had to fight to win," said Dimitrov, who was champion in Brisbane and a semi-finalist at the Australian Open in January.
Belgian third seed David Goffin comfortably beat Andrey Kuznetsov 6-3, 6-2
"I am feeling good. I'm playing really well and pleased with the victory, especially against Andrey -- a good indoor player," Goffin said.
"He can play fast, so it was not an easy first round. I served well when I needed to and I am happy to win my first match in Rotterdam. I had a great week in Sofia (finalist against Dimitrov) and I've come here with a lot of confidence."
Richard Gasquet put out Viktor Troicki 6-4, 6-2, ending with a pair of picture-perfect backhand passing shots.
In the second round, defending champion Martin Klizan battled to a 6-7 (5/7), 6-4, 6-1 defeat of 2016 semi-finalist Philipp Kohlschreiber while French sixth seed Jo-Wilfried Tsonga dismissed Gilles Muller 6-4, 6-2.
Frenchman Pierre-Hughes Herbert advanced past qualifier Evgeny Donskoy of Russia 6-2, 7-6 (7/4).