Valencia - Colombian Alejandro Falla has thrashed sixth seed Gilles Simon for the loss of just one game to progress to the second round on the Valencia Open on Tuesday.
Simon had won both the previous encounters between the pair, but failed to take his chances as he passed up five break points on the Falla serve before slumping to a 6-0, 6-1 defeat in little over an hour.
There were no such upsets for Jerzy Janowicz and Nicolas Almagro, though, as both progressed in straight sets.
Wimbledon semi-finalist Janowicz had to overcome a stiff test from Spaniard Pablo Carreno Busta, but the Pole's typically dominant serve was on song as he fired 14 aces on his way to a 7-5, 7-6 (9/7) win over the world number 66.
Janowicz will now face Joao Sousa in the last-16 after the Portuguese beat Guillermo Garcia Lopez 6-3, 7-5.
Number three seed Almagro stayed on course for a potential semi-final meeting with Janowicz or David Ferrer with a 6-2, 6-3 success over compatriot Pablo Andujar.
Almagro was completely dominant in the first set and despite losing his own serve for the only time in the match early in the second, he broke Andujar three times to close out a comfortable victory.
There was more disappointment for Australian Bernard Tomic as his frustrating year continued when he was forced to retire in the third set against Mikhail Youhzny with the Russian leading 3-6, 6-4, 4-1.
And it wasn't a good day for home favourites Fernando Verdasco and Feliciano Lopez as they fell in straight sets to Michal Przysiezny and Julien Benneteau respectively.
Top seeds Ferrer and Tommy Haas begin their campaigns in the coastal Spanish city on Wednesday.
Ferrer faces an extremely tough first round tie with Gael Monfils as he aims for a fourth title in Valencia, whilst Haas faces compatriot Philipp Kohlschreiber as he continues his quest to make it to the ATP World Tour Finals in London next month.
Results from the second day of the ATP Valencia Open on Tuesday (x denotes seeding):
Michal Przysiezny (POL) bt Fernando Verdasco (ESP) 6-3, 7-6 (7/1)
Joao Sousa (POR) bt Guillermo Garcia-Lopez (ESP) 6-3, 7-5
Jerzy Janowicz (POL x5) bt Pablo Carreno (ESP) 7-5, 7-6 (9/7)
Julien Benneteau (FRA) bt Feliciano Lopez (ESP) 6-3, 6-1
Mikhail Youzhny (RUS) bt Bernard Tomic (AUS) 3-6, 6-4, 4-1 retired
Nicolas Almagro (ESP x3) bt Pablo Andujar (ESP) 6-2, 6-3