Rodrigo opened the scoring, latching on to a terrific through-ball from Ruben Amorim, but it was Luisao's penalty area prowess that eventually proved the difference between the two sides.
|LUISAO'S KEY MATCH STATS|
The Brazilian's first goal of an evening to remember was a powerful header to double Benfica's advantage, which saw the home fans go from nervously biting their nails to outright displays of their frustration with their own players.
Christian Eriksen threatened to spark a Spurs comeback with a sublime free kick - but Luisao had other ideas, cannoning into the back of the net from close range with just six minutes left on the clock.
The 33-year-old is a veteran, not just in Benfica terms but in European clashes too: the tie in north London on Thursday was his 117th appearance in European competition.
Winning European games is great, winning European away games is even better, but winning European away games with your captain the key figure in both defence and attack is the icing on the cake.
Luisao, who has 44 caps for Brazil, will undoubtedly hope his two goals have ended Spurs' hopes of reaching the quarter-final stage for a second successive season, with the Premier League outfit now needing to score at least three goals at the Estadio da Luz, where no team has won during the 2013-14 season so far.