Kai Havertz became the first player to score his maiden Champions League goal in the final since Ilkay Gundogan in 2013 when he broke the deadlock for Chelsea against Manchester City on Saturday.
Germany international Havertz – a big-money signing from Bayer Leverkusen ahead of the 2020-21 campaign – put Thomas Tuchel's side ahead three minutes before the interval in Porto.
The 21-year-old had made 20 appearances in the competition with the Blues and Leverkusen without scoring prior to that strike.
He was teed up by Mason Mount, who became the first English player to provide a Champions League final assist since Manchester United's Wes Brown against the Blues in 2008.
Havertz is the youngest German player to have netted in the European showpiece match since Lars Ricken for Borussia Dortmund against Juventus in 1997.
Thiago Silva, meanwhile, became Chelsea's oldest player to appear in a major European final, aged 36 years and 249 days. He overtook Claude Makelele, who was 35 years and 93 days when he faced United 13 years ago.
The defender's game ended early, however, the Brazil international substituted with an injury in the 39th minute.