Stefanos Tsitsipas put a Rafael Nadal hammering behind him by beating Pablo Andujar in the first round of the Estoril Open and Marco Cecchinato produced more heroics at the BMW Open on Tuesday.
Tsitsipas was riding on the crest of the wave at the Barcelona Open last week, beating the likes of Dominic Thiem en route to a maiden final before world number one Nadal subjected him to a 6-2 6-1 hammering.
The 19-year-old from Greece vowed to learn from a brutal lesson dished out by Nadal on Sunday and overcame Andujar 7-6 (7-2) 6-3 two days later.
Tsitsipas won 71 per cent of points on his first serve, breaking twice in the second set to advance after bossing a first-set tie-break and will now face top seed Kevin Anderson.
Joao Sousa finally claimed a victory at the fourth attempt in the tournament in his homeland, beating eighth seed Daniil Medvedev 7-6 (7-1) 7-5.
Albert Ramos-Vinolas was another seed to crash out, going down 6-2 6-4 to Federico Delbonis, while Cameron Norrie sent sixth seed Robin Haase packing and Nicolas Jarry ousted Leonardo Mayer.
Cecchinato beat John Millman in the Hungarian Open final as a lucky loser last weekend and maintained his momentum with a 5-7 6-3 6-2 success over fellow Italian and fifth seed Fabio Fognini.
Gael Monfils also bowed out in Munich, Mirza Basic defeating the seventh seed 6-2 3-6 6-3, but Philipp Kohlschreiber got past Ivo Karlovic 7-5 6-4 in his homeland.
Yuichi Sugita was another seed to make an early exit, the 119-ranked Yannick Maden coming from behind to win 4-6 7-6 (11-9) 6-2.
Millman missed out on a maiden ATP title when he was beaten by Cecchinato in Budapest and fell at the first hurdle in the Istanbul Open, Dusan Lajovic beating the Australian 6-4 6-0.
Malek Jaziri will face defending champion Marin Cilic in round two in the Turkish city after dispatching fellow Turk Marsel Ilhan 6-1 6-2 and seventh seed Jiri Vesely breezed through at the expense of Daniel Gimeno Traver.