Jurgen Klopp opted not to use Trent Alexander-Arnold against Barcelona on Wednesday. It was a complicated decision but one he eventually got wrong.

The logic behind Klopp starting Joe Gomez at right-back is obvious. This was the first leg of a Champions League semi-final. It was away at Barcelona. Barcelona’s left flank is their most dangerous, thanks to Jordi Alba’s overlapping runs.

(Photo by Andrew Powell/Liverpool FC via Getty Images)

The idea of Alba and Philippe Coutinho doubling up on Alexander-Arnold was a scary one, and so Klopp’s choice made sense. Gomez is, after all, a more solid defender.

At half-time, you’d have to say Klopp was right. Gomez put in some good blocks, tracked his man well, and even though the goal came from his side, it certainly wasn’t his fault.

But once Liverpool were down, they could really have used Alexander-Arnold. We covered before the game how crosses into the box and passes from deep can hurt Barcelona.

(Photo by Stu Forster/Getty Images)

These are both things the 20-year-old does very, very well. He was off the pitch while Liverpool had their period of dominance in the game, however, and it made a difference.

 

All the threat had to come down the left as Gomez couldn’t really help. That limited a side trying to break down a very good defence, removing a lot of width and threat.

At the end of the game, too, as Liverpool desperately searched for an away goal, Gomez was found lacking at full-back. He frequently had to go backwards, put in a poor cross or simply couldn’t beat his man.

(Photo by Chris Brunskill/Fantasista/Getty Images)

Again, Liverpool could really have used Alexander-Arnold.

It was a difficult decision, of course, and one that Klopp did get right at the start. But by the time things had turned, Liverpool really could have used him.

There’s little doubt that Klopp will use Alexander-Arnold when Liverpool host Barcelona next week. He can’t afford not to.