Juventus have it all to do to remain in the Champions League after Andrea Pirlo's side fell to a 2-1 defeat in their last-16 first leg tie with Porto.
Porto made a lightning start to the contest and led after just 61 seconds thanks to a gift from Rodrigo Bentancur. The Juve midfielder sold his back pass short to Wojciech Szczesny and Mehdi Taremi intercepted to slide home from six yards out.
Juventus' pain was compounded when Giorgio Chiellini hobbled off with a suspected calf problem, and at the interval Andrea Pirlo's side were deservedly trailing in what was perhaps their worst 45 minutes of the season.
But worse was yet to come. Immediately after the restart, Porto doubled their lead as the visitors were caught sleeping from kick-off once again. Wilson Manafa drove down the right flank and cut it back for Moussa Meraga, who beat Szczesny at his near post.
It was barely deserved but Juventus managed to grab an all-important away goal with just eight minutes remaining when Federico Chiesa turned in Adrien Rabiot's cross.
Elsewhere, Luuk de Jong grabbed a late goal to give Sevilla hope as Dortmund won 3-2 in Spain in their first leg Champions League last 16 tie.
Sevilla looked like they were on their way to victory when Suso struck from outside the box, two deflections taking the effort past Marwin Hitz.
From there, Dortmund rallied and Mahmoud Dahoud leathered a crisp strike from outside the box into the top corner to level, before two swift counter-attacking moves were converted by Erling Haaland. Bono had not conceded a goal in over 10 hours before this match, and in less than half an hour he had now let in three.
In the second half, Dortmund briefly threatened on the break, and Sevilla then threw on three subs with half an hour remaining as they tried to salvage the match ahead of the second leg.
While Dortmund looked to find their way through on the break, Julen Lopetegui’s side were unable to find much rhythm in attack as the German side focused on maintaining a two-goal lead to take back home for the second leg.
With minutes remaining of the match, De Jong popped up at the back post for a simple finish to volley home and give Sevilla a chance going into the second leg.