Lionel Messi once again showed why he's called the GOAT against Manchester United in the Champions League on Tuesday.A brace from the Argentina international fired Barcelona to a 3-0 victory at the Camp Nou, meaning they won 4-0 on aggregate and reached the semi-finals.Messi's second goal was fortunate - David de Gea made a rare mistake as the ball squeezed under his body - but there was nothing lucky about his 16th-minute opener.An intercepted pass from Ashley Young fell straight to Messi, who nutmegged Fred, ran across the 18-yard box and curled a shot into the bottom-left corner.The 31-year-old has scored hundreds of goals like it, and yet United's defenders could do nothing to stop him.Four minutes later he made it 2-0 before Philippe Coutinho added a third from 25 yards out on the hour mark.Messi has inevitably stolen headlines since the game, with Barcelona manager Ernesto Valverde refusing to apologise for the fact they're so dependent on him."He always gets us out of trouble and we're not going to apologise for having him," the Spaniard said of Messi in his post-match press conference."Leo always turns up in the important games, not just in the big moments but throughout the whole game. He is always capable of scoring but he also drives the team's attack."Gary Lineker, Rio Ferdinand and Owen Hargreaves were BT Sport's pundits for the game and just like the rest of us, they were astonished by Messi's performance.BT have now released their 'No Filter UCL' footage and it features Lineker's reaction to Messi's stunning opening goal.In the video below at 2:06, Lineker looks amazed as he turns away from the Camp Nou pitch and clearly says, "Oh my God," with his hands on his head.

We all know how you feel, Gary.

Lineker followed up his reaction by tweeting: "The incomparable Messi gives @FCBarcelona the lead. The nutmeg alone was exquisite, the finish sublime. Nobody else can do this s**t."

He later added: "Watching Messi live makes life worth living."