Porto's triumph over Roma in their Champions League playoff will ensure goalkeeper Iker Casillas has the chance of playing in the competition for a remarkable 18th consecutive season.
Former Manchester United star Ryan Giggs is the only player to have achieved the feat before his retirement in 2014.
Porto won 3-0 at Roma in Tuesday's return leg of their playoff for a 4-1 triumph on aggregate, a success that put the Portuguese team in the group stage of Europe's elite club competition.
Casillas, a long-time Real Madrid goalkeeper before his switch to Porto last summer, made key saves in the opening half to deny attempts from Roma's Radja Nainggolan and Mohamed Salah.
Casillas tweeted, 35, after the game: "Victory in Rome and qualification for the Champions League, great team!!!"
He added: "I've been in the Champions League for many years now and it's important to be in Europe's biggest competition. We've got big ambitions."
Casillas lifted the Champions League trophy three times during his 16 seasons at Real Madrid.
The Spain international made his debut in the competition in September 1999 against Olympiakos.
Prior to that, at 16, Casillas was included in Real's traveling squad for a Champions League game in Norway as the backup to Santiago Canizares.
No player has made more Champions League appearances in the group stage and final rounds than Casillas, who has made 156.
Real's Cristiano Ronaldo is second in the list after Casillas with 127 appearances.
Two-time Champions League winners Porto last lifted the title in the competition in the 2003-04 campaign, under then-manager Jose Mourinho.
"We are where we deserve to be, in the Champions League, among the best in Europe," Porto coach Nuno Espirito Santo said.
"There is no euphoria, there are objectives we reached, and we want more nights like this one in the future."
The draw for the Champions League group stage will be on Thursday.
