Davydenko, twice a semi-finalist in Barcelona, was devastating when receiving, breaking six times. The 31-year-old could be a stern test for Berdych, having won nine of his 12 matches against the Czech on the ATP Tour.
Two qualifiers, Ernests Gulbis and Dmitry Tursunov, advanced into round two with victories over Radek Stepanek and Denis Istomin respectively.
Awaiting them are two clay court experts from Spain – Fernando Verdasco will take on Gulbis and David Ferrer will face Tursunov.
Rafael Nadal, gunning for an eighth title in Barcelona, is the top seed and favourite, and will begin his campaign later in the week.
Barcelona Open results
Pablo Andujar (Spain) beat Grega Zemlja (Slovenia) 6-7(8) 7-6(3) 6-2
Nikolay Davydenko (Russia) beat Roberto Carballes (Spain) 6-1 6-4
Guillermo Olaso (Spain) beat Gerard Granollers (Spain) 6-4 1-6 6-4
Albert Montanes (Spain) beat Ricardas Berankis (Lithuania) 6-4 6-3
Pablo Carreno (Spain) beat Robin Haase (Netherlands) 6-1 2-6 7-6(5)
Ernests Gulbis (Latvia) beat Radek Stepanek (Czech Republic) 7-6(4) 6-2
Dmitry Tursunov (Russia) beat Denis Istomin (Uzbekistan) 6-3 6-4
Paolo Lorenzi (Italy) beat Guillaume Rufin (France) 6-4 6-2
Ivan Dodig (Croatia) beat Aljaz Bedene (Slovenia) 6-7(6) 6-3 6-2
Andrey Kuznetsov (Russia) beat Igor Sijsling (Netherlands) 6-1 6-3
Bucharest International results
8-Viktor Troicki (Serbia) beat Marinko Matosevic (Australia) 7-6(5) 6-3
David Goffin (Belgium) beat Adrian Ungur (Romania) 6-3 6-1
Daniel Brands (Germany) beat Tatsuma Ito (Japan) 6-3 6-4
Marrakech Grand Prix results
Chanelle Scheepers (South Africa) beat 2-Sorana Cirstea (Romania) 6-3 6-1
Maria Teresa Torro (Spain) beat Arantxa Rus (Netherlands) 6-1 6-1