Iker Casillas’s own goal earned Borussia Dortmund a 1-0 win over Porto and confirmed their UEFA Europa League round of 16 place, according to UEFA’s official website.

Trailing 2-0 from the first leg, the home side started at breakneck speed, but as the heavens opened in northern Portugal, their hopes of progressing were all but extinguished. Casillas produced a wonderful save from Marco Reus’s volley, yet the ball cannoned off him and into the net after Pierre-Emerick Aubameyang’s follow-up had crashed off the crossbar.

Away goal secured, Dortmund sat back. Evandro fired wide following a mazy run before Silvestre Varela’s header forced visiting keeper Roman Bürki into a full-length save just before the break. Vincent Aboubakar’s impish flick was well smothered by Bürki as Porto continued where they left off, though Dortmund menaced on the counter, Aubameyang and Henrikh Mkhitaryan both having efforts disallowed for offside.

Bürki produced another smart stop late on to deny Porto a consolation before home substitute Yacine Brahimi rattled the crossbar and Mkhitaryan saw his attempt smash against the post.