Ashley Williams says the foundations for Swansea's 3-1 Championship play-off win over Nottingham Forest were laid in the 0-0 first-leg away draw.
Williams praised the three "wonder goals" that send the Swans to the play-off final at Wembley on Monday, 30 May.
But he added: "That performance up at their place - that's where we won it."
Stephen Dobbie scored their second goal, but said boss Brendan Rodgers was right to replace him after Robert Earnshaw brought Forest back to 2-1.
Dobbie said: "The aggregate score shows that he [Rodgers] got the right idea. It's obviously not nice coming off, but full credit to the boys they were fantastic again.
"Tactically the manager got it right. Obviously the manager had to square up the midfield and I was the one that had to be taken off."
Dobbie will now be at Wembley for a play-off final for the second successive season, having been on-loan at Blackpool when they saw Cardiff City off 3-2 in last season's promotion tie.
The Scotsman returned to Liberty Stadium after Rodgers succeeded Paulo Sousa - who had loaned him out - at the start of this term.
Dobbie could now line up against the Bluebirds again, if Dave Jones' men can overcome Reading in their play-off semi-final on Tuesday, 16 May.
And he says going to Wembley will hold no fears for the Swans.
"It's been a crazy ride the last two years and just looking forward to it again.
"I enjoyed up to 10 minutes before the end - Forest were pressing us and did really well and luckily we got the break and it hit the other side of the post, so the boys dug in and we got the final goal.
"We're ready to go to Wembley. The boys we've got here play at a high level and they've been to big stadiums so it'll be no different who we play [in the final].
"It's just going to be a fantastic day for the fans and hopefully we can get to the Premiership."
Defender Williams added: "I've never been involved in anything like this before so we'll just try to enjoy ourselves now.
"Everyone's buzzing - I've seen it before and to be part of it is just amazing."