This saying remained famous among us" Lupescu was eventually brought to Rapid București by coach Nicolae Roșculeț where he debuted in Divizia A on 16 September 1962 in a 4–2 victory against Farul Constanța.

[4][8] Lupescu also won two Balkans Cup and the 1971–72 Cupa României, being used all the minutes by coach Bazil Marian in the 2–0 win over Jiul Petroșani from the final.

[4] Lupescu earned 20 caps and scored two goals for Romania, all under the guidance of coach Angelo Niculescu, making his debut on 25 June 1967 in a 1–0 home loss in front of Italy at the Euro 1968 qualifiers.

[1][15] Angelo Niculescu also used him in all the minutes of the three group matches from the 1970 World Cup final tournament as Romania did not advance to the next stage.

[1] He played eight matches and scored two goals at the 1972 Euro qualifiers, managing to reach the quarter-finals where Romania was defeated by Hungary, who advanced to the final tournament.