Liverpool made a nightmarish start against Real Madrid in the Champions League.The Reds made the trip to the Estadio Alfredo Di Stefano as major underdogs given their undulating form in the Premier League, but there was still quiet optimism that Europe might treat them better.However, there was no reason to suggest that was the case during a damning opening 45 minutes in the Spanish capital, falling 2-0 down before the interval against Zinedine Zidane's men.

Alexander-Arnold's first-half nightmare

Los Blancos took the lead through Vinicius Junior, who profited from an outrageous pass by Toni Kroos, but it was the performance of Trent Alexander-Arnold that everybody talking.

In a month where his exclusion from the England squad sparked debate amongst football fans, the Liverpool right-back looked all at sea as he dropped a major clanger for Real's second goal.

As Kroos played yet another long ball over the top, Alexander-Arnold attempt to prevent the pass from reaching Ferland Mendy, but proceeded to bungle his headed clearance into the centre.

Alexander-Arnold struggles vs Real Madrid

It couldn't have been worse timing either with Alexander-Arnold's wayward header meeting the run of Marco Asensio, who proceeded to run clear of Nathaniel Phillips and Ozan Kabak.

And with Alexander-Arnold watching on helplessly from the Madrid turf, the Real Madrid midfielder made absolutely no mistake with a calm and collected finish past Alisson Becker.

Combine that with being comfortably beaten by Ferland Mendy's piece of skill earlier in the half and it's fair to say that Alexander-Arnold didn't cover himself in glory. Check out the key moments below:

Ouch. Not your finest moment, Trent, it must be said.

Fans react on Twitter

And with the England debate fresh in everybody's mind, it will come as absolutely no surprise that many fans on social media were quick to cast their opinion on Alexander-Arnold defensive display.

Whether they were declaring that Gary Neville's MNF analysis was correct or that Southgate should think twice about picking the Liverpool man, you can check out some of the reaction down below:

Still cause for optimism

However, let's zoom out for a second because as undeniably poor as Alexander-Arnold's errors were, hence we're here in the first place, one can't help feeling that it's an 'imperfect storm'.

Sure, we can't get away from the fact that Alexander-Arnold's display in Madrid hasn't exactly been anomalous this season, but I'll happily die on the hill that the 22-year-old is a top, top defender.

Besides, clangers happen to the best of players and the situation is only exacerbated by the immediacy of Southgate's decision, which could ultimately impact whether he goes to Euro 2020 or not.

But this is Liverpool we're talking about and if any club loves a European comeback, then it's them and let's just say that Alexander-Arnold has something of a reputation when it comes to helping out.

If only it was Spanish opposition and the second leg was at Anfield. Huh.