The defender revealed he was far from fully fit for last night's epic penalty shootout win over Bayern Munich and elected to play though the pain after more than a month on the sidelines.
Yesterday's match saw Luiz and Gary Cahill both make their comebacks from injury, with the pair Chelsea's only recognised senior centre-halves.
They came through their first full training session on Tuesday but, by Thursday, Luiz was beginning to struggle.
He said: "I was out for 35 days and I came back but, two days before the final, I had pain again in my leg and there was a chance that maybe I wasn't going to play.
"The day before, I had a test to see if I could play and then I ended up playing 120 minutes."
Luiz insisted he had no intention of asking to be left out, something that would have left the Blues with a real defensive crisis.
"It was a bad situation but I worked hard all of my life," said the Brazil star.
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"When I was a kid, this was my dream and I play with the heart and I'm so happy to end up with the Champions League."
Luiz showed no sign of discomfort when he rammed home the penalty that got Chelsea back into last night's shootout.
"I always try to help the team," he said.
"I missed the final games (of the season) and I was so sad, but this penalty was waiting for me.
"I had another opportunity, I scored and I was happy with this."
Luiz's family flew over from Brazil to watch last night's [Saturday] game.
"It was great to have my family here," said the 25-year-old, before turning on Chelsea's critics.
"All season, guys tried to kill Chelsea, speaking about old players and (saying) the young players don't have the experience.
"Now Chelsea have shown the whole world who Chelsea are."