Lampard netted a first-half penalty at Stamford Bridge before Victorio Maxi Pereira was given his marching orders – but Javi Garcia levelled for the home side late on to set up a tense finale.
However, substitute Raul Meireles’ breakaway goal secured Chelsea’s progression and set up an enticing showdown with Pep Guardiola’s side in a fortnight’s time.
“Obviously they’re going to be favourites because of the way they’ve been playing but we’ve got a lot of belief in ourselves here,” Lampard told ITV.
“We know we’ll have to perform at out absolute best to get a result and we believe we can do that.
“They’re the greatest team in the world, they have been and still are at this present time. That game [in 2009] is still in our mind obviously but this is a completely different year so we need to try and beat them this year.”
Lampard had doubled Chelsea’s aggregate lead from the spot in the 21st minute after Ashley Cole was barged over by Garcia in the box.
But Benfica, despite being reduced to 10 men when Pereira was shown a second yellow card for a reckless challenge on John Obi Mikel, battled hard and equalised when Garcia nodded home from a corner in the 85th minute.
Chelsea’s nerves were finally settled in the 90th minute, when Meireles smashed home the winner after a swift break by Roberto Di Matteo’s side.
“It was a tough game,” said Lampard. “Even though 1-0 away was a great result, it leaves you in a bit of conundrum about how to approach the game.
“We gave them a bit of an idea that they could come and win the game but we’re relieved to get though.
“We created enough chances in the second half to wrap it up without dominating the game and when you see those chances going past the post, you understand that if they get their goal, it’s going to give you a dodgy few minutes.
“They’re a good team, we have to give them respect, but we’re pleased to be in the semis.”
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