Rangers paid tribute to former player Fernando Ricksen before beating Feyenoord 1-0 on an emotional night at Ibrox in their Group G opener. James Tavernier missed a penalty and the only goal came courtesy of a spectacular first-half strike from Sheyi Ojo. Porto defeated Swiss side Young Boys 2-1 in Portugal in the other Group G game.
Celtic kicked off with a 1-1 draw away to French side Rennes in Group E. Ryan Christie equalised from the penalty spot after their hosts had gone ahead through a first-half penalty. CFR Cluj beat Lazio 2-1 in Romania in the other Group E fixture.