Barcelona s Andreas Christensen, left, Ronald Araujo, center, and Gavi are seen after the end of the Europa League playoff first leg soccer match between Barcelona and Manchester United at the Camp Nou stadium in Barcelona, Spain, Thursday, Feb. 16, 2023. The game ended 2-2. (AP Photo/Joan Mateu Parra)
Marcos Alonso sent Barcelona in front with a header but the superb Marcus Rashford drilled home to level for the visitors and helped force a Jules Kounde own goal which gave United the lead.
Raphinha's cross flew in to pull Barcelona level and they might won the game when Andreas Christensen hit the post late on, while the hosts also wanted a penalty after Fred appeared to handle in the box.
Xavi Hernandez and Erik ten Hag's sides are two of the most in-form teams in Europe and delivered a remarkable spectacle.
Having twice clashed in Champions League finals in 2009 and 2011, this Europa League duel offered an enthralling test of each team's recent improvements.
Xavi surprisingly dropped Christensen and Alejandro Balde for Alonso and Jordi Alba, starting with Ronald Araujo at right back.
United deployed in-form Rashford up front, with Wout Weghorst playing in a withdrawn role as an atypical No 10.
The visitors were without a host of players including Christian Eriksen, Antony and the suspended Lisandro Martinez, while Barcelona were missing injured duo Ousmane Dembele and Sergio Busquets.
David de Gea parried a Robert Lewandowski drive early on as Barcelona started the stronger, with Alonso curling over a free-kick and Pedri volleying off-target.
The Red Devils soon improved, with Frenkie de Jong deflecting a Jadon Sancho effort narrowly wide of his own goal.
Barcelona goalkeeper Marc-Andre ter Stegen, in sparkling form this season, made a superb save from Weghorst when through on goal and then denied Rashford.
At the other end De Gea saved from Alba as he burst into the area, before Barcelona lost midfield maestro Pedri to a thigh injury before the break.
Raphinha lashed a spectacular effort inches wide before setting up Alonso from a corner, with the Spaniard heading Barcelona in front after 50 minutes.
The defender escaped the attentions of Fred at the far post and celebrated by raising a finger to the sky in a tribute to his father, a former Barcelona player, who died last week.
However Rashford pulled United back level with a sharp near post finish past Ter Stegen after breezing past Alonso just two minutes later.
United took the lead before the hour mark when Rashford drove into the box and his cross was flicked on, with Kounde inadvertently shouldering the ball into his own net.
This time Barcelona battled back.
Raphinha, playing well in the absence of Dembele, curled a vicious cross into the area which flew past Lewandowski and into the far corner to level.
Christensen hit the post and De Gea made a fine save to foil Ansu Fati late on as Barcelona took control in the final stages but could not find a winner.
Xavi warned in his press conference that the game would not be won or lost in the first leg, and it is perfectly poised for the second leg at Old Trafford next week.
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