Liverpool captain Steven Gerrard says he and the players regret conceding two goals against Notts County on Tuesday night, which forced the game into extra time.
Liverpool 4-2 Notts County aet.
The Reds eventually overcame the League One side 4-2 after extra time to progress to the third round of the League Cup, where they will meet Manchester Utd next month.
The game also saw three injury blows for the Reds with Aly Cissokho, Joe Allen and Kolo Toure all being forced off the pitch carrying problems.
“There’s no doubt playing extra time was a blow for us,” Gerrard is quoted in the Liverpool Echo as saying.
“Kolo’s injury came in extra time. He wouldn’t have done that during normal time. We have ourselves to blame for his injury. We have to take responsibility for that.
“There’s an international break coming up, so fingers crossed he doesn’t miss that many games for Liverpool.”
Looking ahead to Sunday’s Premier League clash against arch rivals Man Utd, Gerrard hoped Toure would be back from his injury to start alongside Daniel Agger in defence.
“Sunday is a massive game. Kolo has started the season very strongly and we will be very disappointed if he is not fit for the weekend.”
Gerrard, as well as Agger and Toure, hit the post during the game on Tuesday night, shots that, had they gone in, would have put the game beyond the visitors.
But Gerrard believes complacency cost Liverpool and ultimately allowed Notts County a way back into the game.
He added, “The game got too easy. When you have a lot of inexperience in your team, you can sometimes take your foot off your gas and get punished.
“We were in complete control and it looked like we were going to win by three, four or five. But when you have a lot of youngsters in your team who maybe don’t know how to see a game out, sometimes you can make it very difficult for yourself and that’s what we did.”
Jordan Henderson meanwhile says the players will take the positives from the game and go into Sunday’s clash against United full of confidence.
Liverpool vs Manchester United in the league gets underway at 1.30pm this Sunday, 1st September 2013. It’s live on Sky Sports in the UK.