With Manchester United and Barcelona facing off for a second time in four years, it is tough to avoid the David de Gea error which helped the Catalan club clinch victory over their Premier League opponents in 2019.
United had made it through to the last eight with a dramatic late win against Paris Saint-Germain on away goals, while Barca cruised past Lyon with a 5-1 home win. In the quarters, though, it was one-way traffic despite Ole Gunnar Solskjaer's side impressing in Paris.
A Luke Shaw own goal was the only goal of the game in the first leg, but United had won on the road in the previous round so all was not lost. A De Gea mistake ended up costing Solskjaer's team, though, while leaving United's goalkeeping coach Emilio Alvarez with egg on his face.
"Those who know David well can tell you one of his virtues is his ability to block everything out, he is very strong mentally," Alvarez told Cadena SER as United prepared to take on Lionel Messi and co. "We do something different when facing Messi.
"With De Gea, we have worked on some more specific work, there are some extras compared to other games with having Leo up front. I wouldn't lie if I said we do a super special preparation.
I worked in La Liga for many years with David as well and before with other keepers. I can't deny that there is a particularity regarding Leo. In the end, you try to offer tools and data to the keeper so that it can help him."
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In light of Alvarez's comments, plenty of eyes were on the Spanish goalkeeper. While De Gea couldn't do too much about Messi's first goal of the evening as the Argentine found the corner from the edge of the box, he won't be happy with how the second found its way into the net.
Messi was on his weaker right foot when he had another pop at goal in the 20th minute, and his shot looked to be too weak and destined for the arms of De Gea. United's stopper failed to get his body behind the ball, though, and it slipped through his hands before trickling over the line.
United's run was already all but over, but Philippe Coutinho made sure for Barca with a long-range stunner just after the hour mark. The Catalan club failed to go all the way, though, suffering a memorable semi-final defeat at the hands of eventual champions Liverpool.
De Gea played in the first leg of United's 2023 clash with Barca and was also named in Erik ten Hag's starting line-up for the return game at Old Trafford. In between those matches was an impressive display against Leicester, which clearly pleased the manager.
"Today was really tough but it was first that Leicester played brilliantly but second that we were rubbish," Ten Hag admitted. "Our way of play we were really inconsistent and ill-disciplined in our principles and rules of the game.
"Then you get problems and it was only because of David De Gea that we get a clean sheet until half-time. We were lucky that we scored a goal. Great ball from Bruno [Fernandes], great run from Rashy [Marcus Rashford]."
