Chelsea boss Jose Mourinho said his side's last-gasp 2-1 win in Valencia was the best away performance in Europe in his time in charge at the club.
Mourinho saw his side score a dramatic last-minute goal
"I was starting to prepare my brain for extra-time but we deserved to win over the 90 minutes, clearly," he said.
"We completely dominated in the second half and they had no chances.
"It is maybe our best performance away from home in three seasons. This is an unbelievable group and what we are doing this season is amazing."
Mourinho added: "I am proud of this group because this is a special season. Nobody has had so many problems as we had. We have had big problems with more than 50% of the team.
"But they resist and resist and mentally they are very strong. I could not be more proud of these players.
"It is an amazing situation for English football with three teams in the semi-finals of the competition.
"But we deserved to win the game over 90 minutes. Santiago Canizares made two unbelievable saves - especially the one against Michael Ballack's header.
This is amazing - we have won a competition and are in two semi-finals
"I thought the team was very strong. I had the changes ready if it went to extra-time. But when I saw the ball in the net in the last minute with Valencia needing to score two, it was great.
"It happened to me when I was at Porto - we scored in Old Trafford in the last moment. Like all goals, there was great emotion.
"Michael Essien is a special player. He is an athlete. He can run forever. He could play a game every day. He is a superb athlete.
"When we lost him one month ago it was a big, big loss. But he was ready to come for this crucial game. I know he is suspended for the next game but this one was the crucial one. The next one is not crucial."
The win means that Chelsea remain challenging on four fronts this season.
The Carling Cup winners are also in contention for the Premiership and FA Cup.
"It was a great performance in the second half, we were under pressure. We were losing 1-0 and it was an unbelievable performance," he said.
Chelsea will be joined in the last four of the Champions League by Manchester United, their rivals for the Premiership crown.
"I am very pleased Manchester United are also in the Champions League semi-finals because they will also have to play two more matches and their focus is also in three competitions," he said.
The Portuguese was also upbeat about the extra games facing Chelsea.
"Being in the semi-final is great for the team, great for the group," he said.
"This is amazing. We have won a competition and are in two semi-finals.
"We have a difficult semi-final on Sunday but hopefully we can be in the FA Cup final and we are still fighting for the Premiership."
Chelsea skipper John Terry admitted that Mourinho had given his players a verbal rocket at half-time, when they went in trailing 1-0.
"We had to be a lot better than in the first half. We were not good enough and we got a kick up the backside.
"We came out in the second half and we dominated. We never gave up and we had said before if we went a goal down it wouldn't change anything."