1 - Manchester United have won just one of their eight European Cup/Champions League meetings with Barcelona (D4 L3), losing both of their last two encounters in the 2009 and 2011 finals. Daunting.
22 - Lionel Messi has scored 22 Champions League goals against English clubs; more than any other player in the competition. Devilish.
4 - Manchester City have lost each of their four games against English opponents in European competition - twice against Chelsea in 1971 and twice against Liverpool in 2018. Warning.
6 - Liverpool are unbeaten in their previous six games against Porto in European competition (W3 D3), with the Reds scoring 12 goals and conceding just twice. Fancied.