Manchester United conceded two late own goals to allow Sevilla to snatch a 2-2 draw in the first leg of their Europa League quarter-final at Old Trafford on Thursday.
Marcel Sabitzer's quickfire double in the first half put Erik ten Hag's team in control of the tie, but Sevilla, record six-times Europa League champions, pulled one back in the 84th minute when Jesus Navas's shot pinged off the feet of Tyrell Malacia and keeper David de Gea into the net.
United were reduced to 10 men when defender Lisandro Martinez was carried off injured and Youssef En-Nesyri's stoppage-time header glanced off Harry Maguire into the goal to give Sevilla a huge lift ahead of next week's second leg.
"I think we had the game in hand," Ten Hag told BT Sport. "We should have scored three or four. . . and then some unlucky moments with injuries. And then we conceded two own goals and that's bad luck. We have to deal with it. Of course, we have to learn that we have to kill the game."
Sabitzer, who is on loan from Bayern Munich, netted his first European goal for United in the 14th minute, when he controlled a pinpoint pass from Bruno Fernandes and shot past keeper Bono.
The Austrian doubled his tally seven minutes later, latching on to a fine pass from Anthony Martial and finishing well.
Juventus took a small step towards the last-four as Federico Gatti's goal in the second half secured the hosts a 1-0 victory over Portuguese side Sporting in the first leg.
Juve's injury woes were further exacerbated by the replacement of Wojciech Szczesny shortly before the break. The Poland international seemed unwell and held his chest before walking off and being replaced by Mattia Perin.
The club said after the match that Szczesny had not suffered any serious problems.