Andy Robertson described Dominik Szoboszlai's attempted backheel that led to Barnsley's goal in Liverpool's FA Cup third-round win at Anfield as "unacceptable".

Liverpool had led the League One side by two goals thanks to stunning strikes from Szoboszlai and Jeremie Frimpong, but Barnsley halved the deficit just before the break. 

After initially doing well to recover the ball, Szoboszlai tried to backheel the ball inside his own six-yard box, allowing Adam Phillips to finish past Giorgi Mamardashvili. 

It was a mistake that increased the tension around Anfield throughout the second half, though late strikes from Florian Wirtz and Hugo Ekitike put Liverpool into the fourth round. 

Arne Slot said conversations would be had with Szoboszlai after his mistake, while Barnsley boss Conor Hourihane described the incident as "disrespectful" to his team. 

And Robertson backed up the thoughts of Hourihane. 

"That's putting it nicely! The frustrating thing is, Dom does an unbelievable 60-yard sprint to start," he said when asked if Szoboszlai's decision let Barnsley back into the game. 

"He's getting the clap off the Kop, and I don't know if that went to his head. We can joke about it now, but it's unacceptable to lose a goal like that. Dom obviously knows that.

"He's been magnificent for us this season, and he was again really good. He just had a lapse of concentration, and we can't afford too many of them in the six-yard box.

"I don't think Gio [Mamardashvili] was too happy. He wants to keep a clean sheet, the defence wants to keep a clean sheet as well, so it wasn't great.

"It gave them a way back in, and it was 2-1 for a long time. It made it a bit nervy, but we got there in the end.

"I think we all said something [to Szoboszlai] at the time, but he realised and apologised at half-time. If anyone's performances can't get criticised this season, it's Dom's.

"He's been 100% every game this season and has this lapse of concentration, which isn't great. We can't really afford that in the so-called bigger games."

Liverpool are now unbeaten in their last 11 games in all competitions (W6 D5), their best run since going 24 unbeaten between September 2024 and January 2025.

However, the Reds have made a habit of giving encouragement to teams despite being in front, evident in their recent clashes with Leeds United and Fulham. 

"That's the most frustrating thing. This season, we've let teams in far too many times," Robertson added.

"From the opening game of the season, we've done it, and we've been punished at times, in terms of losing or drawing games.

"At 2-0, we started looking in control, so for that to happen, then questions get asked. It's safe to say it was an individual error, but we then limited their chances, which is good.

"Then it was just about getting the third and fourth. We had quality off the bench, and they delivered. These games are about getting through.

"We've seen a couple of Premier League teams going out against lesser opposition, and thankfully, it wasn't us. We've done better over the last couple of weeks.

"We've looked a bit more secure defensively, which is pleasing, but now we need to put it all together because people are saying we're lacking an attacking threat.

"We need to now get both because, at the start of the season, we were really good going forward, but probably a little bit too open at the back. Now we've kind of reversed it.

"If you want to win trophies and go further in tournaments, you have to get the perfect balance, and that's what we're working towards."