Uefa has announced that this season's Champions League, suspended in March because of the Covid-19 pandemic, will be completed with an eight-team mini-tournament to be held in Lisbon in August.
Instead of the usual two-legged format for the quarter-finals and semi-finals, the 2019/20 edition will see both stages played over one leg, with the final to be held on August 23.
Following an executive committee meeting held by video conference, Uefa deputy general secretary Giorgio Marchetti said the four last-16, second leg matches which still have to be played - Manchester City v Real Madrid, Bayern Munich v Chelsea, Juventus v Lyon and Barcelona v Napoli - will take place on August 7/8, either at the originally scheduled venues or in Portugal.
Paris Saint-Germain, Atletico Madrid, Atalanta and RB Leipzig have already qualified for the last eight.
The plan means there will be six fewer games in European football's most lucrative competition, which will cost Uefa broadcast revenue.
Uefa president Aleksander Ceferin said he expected matches to be played without fans, although there was a small chance that could change.
"We don't think we can have spectators but things are changing rapidly and we will assess the situation at the beginning of January." he told a video news conference.
"One month ago, I couldn't even say if we could play the competition."
He added there was no plan B in case the public health situation in Portugal worsened although Uefa was monitoring the situation daily.
Istanbul, which was due to host the 2020 final, will now instead be the venue for the 2021 edition, with all other scheduled hosts moving back a year, Uefa said.
A similar format will be used to decide the Europa League competition at German venues from August 10 to August 21.