Liverpool boss Brendan Rodgers accused his team of being “lazy” and warned their defending must improve after a 3-2 home defeat to Udinese.
The hosts had deservedly taken the lead in the first half of the Europa League Group A clash thanks to Jonjo Shelvey's 23rd-minute strike, but their opponents' captain and talisman Antonio Di Natale levelled in the opening minute of the second period, finishing a move that had started when Reds defender Glen Johnson lost possession.
Anfield was then left stunned as Sebastian Coates' 70th minute own-goal and Giovanni Pasquale's finish from Di Natale's tee-up two minutes later put the Italian side firmly in the driving seat.
Substitute Luis Suarez swiftly replied direct from a free-kick with 15 minutes to go, but it proved only a consolation.
Reflecting on Liverpool's display, Rodgers said: "We are disappointed with the result because for large periods of the game we were the better side, but we have to defend better.
"It was very frustrating.
"We lost our concentration at the beginning of the second half and I thought we'd moved on from that to be honest.
"I thought we were just lazy - that is the easiest way to describe it.
"Just lazy in our play and loose and sloppy. It is as simple as that."
Rodgers had highlighted the threat posed by Di Natale in the build-up to the match and, when asked about the inspirational performance the 34-year-old had put in, the Liverpool manager said: "The guy has qualities, there is no getting away from it.
"It was a very good finish for the first goal. With the third I think we gave him a wee bit too much time, but he is a quality player.
"But I'll always only concentrate on my own players and where they can improve and be better.
"They give me and the team everything, but at critical moments of the game - in particular at the start of the second half - we needed to be solid and tight, and we gave away three goals."
Di Natale was back in the Udinese team after being axed from the squad for last weekend's Serie A draw with Genoa by coach Francesco Guidolin, his punishment following a dressing-room outburst.
Asked about Di Natale after the win at Anfield, Guidolin said: "We know he is a wonderful player, an outstanding player - I have said this time and time again.
"And in any case, this Di Natale issue is something we thought was over a while ago.
"What I really liked was my team's reaction in the second half. I tried to give my best during half-time in the dressing room to coax them along."
Liverpool stand third in Group A after two fixtures, on three points, one point behind Udinese and leaders Anzhi Makhachkala.