Wycombe striker Jermaine Easter admitted he had expected Charlton to put up more of a fight after knocking the Barclays Premiership side out of the Carling Cup last night.
The Addicks, second-bottom in the top flight, never got going as the Coca-Cola League Two side out-battled them from kick-off to earn a semi-final place.
Easter chalked up his fifth goal of the competition 10 minutes before half-time, capitalising on some careless play from the hosts.
The 24-year-old felt the Chairboys, cheered on by a 4,000-strong travelling support, deserved their victory.
Easter said: “I would say this is probably the most important goal of my career so far.
“I did think it was going to be harder.
“Obviously they are struggling in the Premiership, but I thought it was going to be tougher than it was.
"As the game went on and we had gone in front, I did not think we were going to lose.
“We could have gone into half time two or three-nil up. It was disappointing in that respect.
“It was a no-pressure game for us and all the lads wanted to just enjoy it.
“We are in the semi-final now and that is massive.”
Wycombe manager Paul Lambert praised the “extraordinary effort” of his side, who had also knocked out Fulham in round two.
“It was certainly not easy from where I was standing and I am sure the players will say the same,” the former Scotland international said.
“It was an extraordinary effort and the lads were absolutely terrific.
“I do not get this thing that ‘it is only Charlton and they are struggling’. They are still a top-class side.
“We came here and gave a good account of ourselves.
“We have punched above our weight. No doubt about it. Nobody expected us to get this far and the players deserve all the credit.”
Lambert was the first Briton to win the Champions League, playing for Borussia Dortmund in 1997.
The 37-year-old quipped: “My kids get bored with that story. It was 10 years ago.
“I have got a group of lads here at the moment who have done me proud and I cannot speak highly enough of them.”
The Wycombe boss added: “What you want from people is giving the maximum effort and running for you. Every match I have been involved in I could never ever fault the effort.”
Lambert hopes his team can now build on this result to sustain a promotion challenge.
“The Charlton match was a bit of a burden. There was too long in between the league games,” said Lambert.
“We are up in the league and will try to see it through as long as we can.
“We are into a semi-final of a national cup competition now, which is terrific.”
Both the Charlton team and their head coach Les Reed were jeered off at the final whistle, with chants of: ‘You’re not fit to wear the shirt,’ and support for axed West Ham boss Alan Pardew’s return to the club he used to play for.
Chief executive Peter Varney insisted before the match no managerial changes will be made this season, with Reed having only replaced Iain Dowie last month.
Around 50 or so supporters continued their vocal protests outside the stadium, braving the cold night in south-east London.
Reed and the players remained locked in the dressing room for more than hour after the final whistle.
There was no club representative present at the post-match press conference.