- Liverpool twice came from behind, with new signing Mohamed Salah on target.
- Klopp says Miguel Britos's late qualiser 'was offside'.
- Watford goalkeeper Heurelho Gomes insisted Watford deserved their point.
Jurgen Klopp claimed Liverpool were wrongly denied a winning start to the Premier League season as Watford snatched a controversial last-gasp equaliser in a dramatic 3-3 draw on Saturday.
Liverpool manager Klopp was furious that Miguel Britos wasn't ruled offside when the Watford defender poked home from on the goal-line after Richarlison's shot was pushed onto the crossbar by Liverpool goalkeeper Simon Mignolet.
Britos's stoppage-time strike capped a roller-coaster encounter at Vicarage Road, which saw Liverpool forced to settle for a point despite twice come from behind to take a 3-2 lead.
"We were unlucky in the end. The equaliser was offside. It's obvious because the linesman is on the line. He needs to see it," Klopp said.
"I cannot change it. We would have had defensive areas we need to work on even if we'd won 3-2, but we were the better team. We should have won."
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As well as complaining about the officiating, Klopp was also frustrated by Liverpool's failure to finish off Watford.
Sadio Mane's 29th-minute effort had cancelled out Stefano Okaka's eighth-minute header, only for Abdoulaye Doucoure to immediately restore the home side's lead.
Liverpool were back level in the 55th minute through Roberto Firmino's penalty and new signing Mohamed Salah put them ahead in the 57th minute.
"The first half I wasn't too happy with. We passed but couldn't see what we actually wanted. The second half was a lot better," Klopp said.
"We forgot to close the game. We defended a little deep. We have to push up."
Watford goalkeeper Heurelho Gomes insisted Watford deserved their point after showing the type of fight that was missing towards the tail end of last season.
"I believed we didn't deserve less," Gomes said on Sky Sports Football. "We fight to the end and that's the spirit we have. We have to make life difficult for any team that comes here, this is our house.
"We have to show Liverpool respect, but they have to show everything to try to win. They did, but we deserve what we got."
Watford's hero of the day Britos said the result should not mask the problems Marco Silva's side face.
"It's very important to start the season with a point," Britos said. "It's always positive when you get something, especially at home. We have to carry on this way, to correct our mistakes. We have a lot of players injured, even today at the start of the season, so I think we can improve."
There were familiar problems at the back for Liverpool, who were dogged by a weakness at set-pieces last season.
"We're disappointed with the result, especially after leading for so long in the second half," said captain Jordan Henderson.
"We've conceded from a set-piece, that's disappointing, that needs to change quickly if we're going to do anything this season. There were a lot of positives at times but as a team we've got to see the game out.
"We were a threat going forward, but again we're talking about set-pieces. We need to be better. We worked on them a lot in the pre-season, but there's only us that can change it."
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