The Algeria winger netted a fine treble that included a superb solo goal and a free-kick as the Portuguese giants opened their UEFA Champions League Group H campaign in style on Wednesday.
"This was the first time I scored three goals," Brahimi told UEFA's official website. "For a first match it is incredible.
"We played very well and we must go on like this. I'm very happy.
"I have to thank all."
Despite witnessing his players record Porto's biggest victory in the Champions League, Lopetegui has played down the significance of the result.
"There's no right formula for success unless working as a team," said the Spaniard.
"We made a strong start, scored early and remained focused from them on.
"We go home mildly satisfied, since there are five games left. Now we are on top of the group, but there's a long way ahead of us."
Porto return to Champions League action at Shakhtar Donetsk, who drew 0-0 at Athletic Bilbao, on September 30.
