Every once in a while, a match comes along that will live in the memory long past the final whistle.

A treat, a feast of football. That is what Barcelona and Inter Milan served up in an enthralling 3-3 draw in the first leg of their Champions League semi-final.

"It was an amazing battle to watch, almost like a boxing match where opposing styles make the fight," said former Liverpool defender Stephen Warnock.

"Barca and Inter were set up very differently, and it made for one heck of a game."

Former Rangers striker Ally McCoist said on TNT Sport: "Tonight was just special, special to be here to watch those two teams.

"We have been treated to some unbelievable football this evening."

Sensational goals, high drama and incredible individual performances - it had everything. Here's how an engrossing evening of football unfolded.

Much of the talk in the build-up to this match was around Barcelona.

Their dangerous high line, their ability to score an abundance of goals with a prolific front three, the prospect of another golden generation of players nurtured from their prestigious La Masia academy.

After 30 seconds of the first leg at the Nou Camp, that all changed.

Marcus Thuram's clever backheel finish was the fastest goal to be scored in a Champions League semi-final and left the home crowd stunned.

But against a side capable of scoring lots of goals, Inter knew one would not be enough and the second came on 21 minutes when Denzel Dumfries fired in a remarkable overhead kick to once again silence the home crowd.

That was not in the script for a Barcelona side trying to reach the Champions League final for the first time in 10 years.

"I think everyone thought that once Inter went 2-0 up, that would be it – they would shut up shop, and we wouldn't see much other than another outstanding defensive display by them," said Warnock.

Inter had conceded just five goals in this season's Champions League and with Barcelona's high-line tactics exposing their own defensive weaknesses, the Serie A side were able to take advantage.

For a few minutes, at least.

Trailing by two after 21 minutes, Barcelona needed an immediate spark.

Enter Lamine Yamal.

The teenager, making his 100th club appearance, took just three minutes to step up for his team and conjure a moment of magic to get them back in it.

Jinking into the penalty box and leaving Henrikh Mkhitaryan in his wake, Yamal struck a majestic left-footed finish that ricocheted off the post and into the net to launch the comeback.

'Get the ball to Yamal' became a clear tactic for Barcelona and watching him take control of the game, pinging balls into the area and constantly making himself available in forward positions, it was easy to forget he is still just 17 years old.

The equaliser came on 38 minutes, when Ferran Torres stabbed in from close range after Raphinha nodded on Pedri's diagonal cross.

Parity restored just in time for the break, the anticipation was heavy after what had been a mesmerising opening 45 minutes.

Former Liverpool player Steve McManaman, part of the TNT punditry team, said: "It had everything. It showed how frail Barcelona are defensively, but going forward they are electric."

With fans and neutrals alike on the edge of their seats from this gripping encounter, expectations were high for an equally entertaining second half.

After three stunning goals worthy of putting any team in the Champions League final, there was almost an air of disappointment when Inter's goal to restore their advantage came from a simple corner routine.

Dumfries rose highest to meet Hakan Calhanoglu's corner at the back post, highlighting Barca's defensive struggles.

"Inter are not the most dynamic team, and they don't have much raw pace but there was still a way for them to hurt Barca, on the break or with set-pieces," said Warnock.

"They are the oldest squad in the Champions League so there is a lot of experience there and they showed that tonight with the way they were clever enough to keep opening Barca up."

At 30 years and 56 days, Inter named the seventh oldest starting XI for a Champions League semi-final game and they used all of that experience to keep cool heads in a high-drama scenario.

"When you play at home like we did, the sensation is that we should have managed to earn a better result," Barcelona forward Raphinha told Movistar Plus.

"We can't concede that many goals, especially at home. Sure, you have to give praise to our opponents who are strong and played well tonight but we are Barca and it's our duty to win at home, that's how it is."

Smarting from three consecutive defeats in the past seven days, where they have dropped to second in Serie A and gone out of the Coppa Italia to city rivals AC Milan, Inter were determined not to let the lead slip away again.

"Barca were set up to attack and take the game to Inter but their high-line left them vulnerable at the back," said Warnock.

"They are not going to change that way of playing - they haven't changed all season and they have done well doing it, so why would they?"

Conceding three goals at home and facing the prospect of travelling to the San Siro with a one-goal deficit, sometimes all you need is someone to take a chance.

That is what Raphinha did when he picked up the ball 25 yards out and hammered the ball into the back of the net, via a touch off the bar and goalkeeper Yann Sommer's back.

Inter had held the lead for all of 114 seconds before Raphinha's equaliser drew Barcelona level for the second time in the game.

Yamal might have been the star of the show on Wednesday but it is Raphinha who has dominated the headlines for Barca throughout this campaign and, although the goal has not been credited to the Brazilian, his performances throughout have proved pivotal to their success.

"I really appreciate what we did today," said Barcelona boss Hansi Flick.

"We played a great game, and of course, the goals we conceded weren't pretty. You have to talk about them, analyse them, but the way we played, our style, our way of playing...it was fantastic."

Mkhitaryan thought he had found a fourth goal when he poked home in the 75th minute only for the video assistant referee to rule it out for an agonisingly tight offside.

But even without that, the game was the joint-highest score draw in a Champions League semi-final game alongside a 3-3 draw between Dynamo Kyiv and Bayern Munich in the first leg in 1998-99.

It sets up a mouth-watering second leg in Milan next week and, while Barca may be disappointed to have conceded three goals at home, the visitors will take confidence that they were able to match them on an exhilarating night of football.

"After three defeats in a row we saw the real Inter tonight," said Inter goalscorer Dumfries.

"We played with heart and I'm proud. Obviously we wanted to win but I think it was a good performance and it's still all to play for. Let's see what happens at the San Siro."