Jurgen Klopp was in bullish mood after Miguel Britos' last-minute header denied Liverpool an opening-day win against Watford.

Klopp claimed the Uruguayan's equaliser, in the third minute of added time, was "clearly offside" and said his side had been "extremely unlucky" at times in the 3-3 draw at Vicarage Road.

The Liverpool boss admitted his side's performance had not been without fault, however, and said Watford's first-half performance in particular had left him frustrated at the break.

He said: "We had our moment, and then we conceded an offside goal. That’s not fun. It doesn’t feel too good. We must do better, and have to do better.

"I wasn’t happy in the first half with the situation when it was obviously too physical. They didn’t create too much – the first one, everyone will say a set-piece but it was a good ball and a good run.

"The second one was unlucky, and a formation problem, if I remember it right, Alberto lost the challenge and [Georginio] Wijnaldum didn't close down. But I also thought if was offside.

"We were extremely unlucky at time sand in the second half scored two wonderful goals.

"If you do everything on the first match, you can’t expect perfection. You have to accept a few things but to use them for the next game."

Despite scoring on his debut, £35-million man Mohamed Salah got little change out of Jose Holebas bar a 20-minute period after half-time, and Klopp conceded that the Greek defender's performance had been impressive.

He said: "Salah struggled at the start against Holebas, who was a big, strong man. We need balls in behind, he has pace to utilise."