The Portuguese outfit scored early in both halves to take a one-goal advantage into the second leg
Juventus head coach Andrea Pirlo was upset that his side gave Porto their opening goal "on a silver platter" in Wednesday's 2-1 Champions League defeat.
The home side scored early in both halves – Mehdi Taremi in the second minute and Moussa Marega in the 46th – before a late goal from Federico Chiesa gave the Serie A side hope.
But Pirlo was still upset with his side's performance in the last-16 first leg, especially the simple mistake in possession that gifted Taremi the opener.
What Pirlo said
“We had prepared well for this game, it was not the attitude we wanted, but conceding a goal in the opening minute when we handed it to them on a silver platter made everything more difficult," Pirlo told Sky Sport Italia.
“When you concede a goal after one minute, a strange one at that, it’s natural the players will lose confidence, especially against a side that knows how to clam up in defence.
"Our approach was wrong after we conceded the goal ... We had planned on attacking the deeper spaces, but if you take too many touches, things get complicated. We weren't smart, the ball was moved around too slowly.
“Porto got the game immediately on the track they wanted. With such a packed fixture list, it’s normal you can’t always maintain absolute focus and the right tempo, but it shouldn’t have happened in the round of 16 of the Champions League.”
Two quick goals prove costly
Taremi's goal – which came after Rodrigo Bentancur's pass sold goalkeeper Wojciech Szczesny short – came after just one minute and three seconds. It was the third-fastest goal Juve have ever conceded in the Champions League.
Marega's strike, coming just 19 seconds into the second half, is the fastest goal Juve have conceded in the second half of a Champions League game.
What's next for Juventus?
Juventus will look to get past Wednesday's disappointment with a run of four Serie A matches, against Crotone, Verona, Spezia and Lazio.
Pirlo's side will then have their chance to overcome their one-goal deficit when they face Porto in the second leg on March 9 in Turin.