Having paced Friday's running, A1 Team Netherlands remained out front during the Saturday practice session after Robert Doornbos posted the quickest time in the Algarve.
The IndyCar ace posted a fastest lap of 1min 30.115secs during the session which put him more than seven-tenths of a second clear of Team Ireland driver Adam Carroll.
While Doornbos' lap was completed with the aid of his powerboost, the Dutchman declared himself happy with the pace shown.
“We continued where we left off yesterday,” said Doornbos. “I was worried about the overnight rain but it turned out that on old tyres we were strong. The quick lap was me getting used to the new PowerBoost system which is not something I've done before, and the car was good.”
Behind Carroll, Neel Jani was third quickest for Switzerland, albeit just over a second off the pace, while home hero Filipe Albuquerque was fourth quickest for Portugal, Italian Vitantonio Liuzzi and American Marco Andretti rounded out the top six.
GBR took to the track having missed the Friday session with technical gremlins, with Dan Clarke down in 18th place – one position behind Felipe Guimaraes for Brazil who suffered a spin during his first foray onto the circuit after the damage sustained by his team-mate during the Friday rookie only session.