Watford 2-1 Leicester City

Argentine midfielder Roberto Pereyra scored his second goal for Watford since joining for £11.2m in August

Watford scored inside the opening 33 seconds as they defeated champions Leicester at Vicarage Road.

Etienne Capoue volleyed the Hornets into the lead - their fastest Premier League goal - before Roberto Pereyra curled in a second after 12 minutes.

Leicester pulled one back when Riyad Mahrez converted a penalty after Miguel Britos' clumsy foul on Jamie Vardy.

But the Foxes could not score again and remain without an away league victory this season.

Leicester become only the third reigning top-flight champions, after Leeds in 1992 and Blackburn in 1995, to start a Premier League season without a win from their opening six away games.

• Relive Watford v Leicester as it happened

A crazy start

Watford had been embarrassed 6-1 at Liverpool in their last match and boss Walter Mazzarri demanded an improved performance.

But even he could not have expected the blistering start they made as they went ahead in the opening minute.

Leicester midfielder Danny Drinkwater, who had missed England's matches against Scotland and Spain with a rib injury, gave the ball away and that enabled Pereyra to sprint down the left wing before his cross was flicked on by Troy Deeney, with Capoue volleying past Ron-Robert Zieler.

Pereyra doubled the advantage shortly after, cutting inside Drinkwater on the edge of the penalty area and curling the ball into the corner.

Leicester fought back with a penalty after only 14 minutes, but were frustrated and denied by a resolute home defence as the hosts held on for the win.

Where have last season's Leicester gone?

Leicester won the league title for the first time in their history last season but looked a pale shadow of that side at Vicarage Road.

Defensively vulnerable and lacking a cutting edge up front, the Foxes slipped to their sixth league defeat of the season, double the amount they had throughout the entire 2015-16 campaign.

One huge concern for Leicester boss Claudio Ranieri would be the form of centre-forward Vardy. Before the game Ranieri said he expected to see a "new Vardy" after he scored in England's 2-2 draw with Spain at Wembley on Tuesday.

However, apart from winning a penalty, which was more down to the reckless challenge from Britos, Vardy looked unlikely to end a goal drought that now stretches to 13 club games.

His only attempt came late on when he shot harmlessly wide and the Foxes need him to rediscover the form that saw him score 24 Premier League goals last season.

Jamie Vardy has not scored for Leicester since the 4-1 loss at Liverpool on 10 September. As this graphic shows, he did not come close to ending that run at Watford with his only attempt at goal well off target

Poor domestically, great in Europe

This result extends a strange, but worrying quirk for Leicester fans - of their side failing to win any of the five matches they have played immediately before a Champions League game.

They remain 14th in the Premier League, but are only two points above the relegation zone, despite impressing in Europe's premier competition.

With 10 points from four Champions League games and without a goal conceded, Leicester are top of Group G and only need two points from their last two games to advance into the last 16. The first of those comes on Tuesday when they entertain Belgian side Club Brugge.

A concern for the Foxes would be that record signing Islam Slimani, who scored the winner in a 1-0 win over Porto, missed the Watford game with what was described as a "slight groin injury".

Man of the match - Roberto Pereyra (Watford)

Pereyra was heavily involved in Watford's first goal and scored the second - his first goal since scoring against Arsenal on his Hornets debut on 27 August

99 not out for Deeney

• Watford captain Troy Deeney remains on 99 goals in all competitions for the club. He has been stuck on this tally since 1 October, having failed to score in his last five appearances

• This was Claudio Ranieri's 50th Premier League game in charge of Leicester. He has won 26, drawn 15 and now lost nine times

• Leicester's Robert Huth made his 300th Premier League appearance, becoming the first German player to reach this milestone

• This was Watford's first Premier League win over Leicester on their fifth attempt. Leicester have won three times with the other match ending in a draw

• Watford manager Walter Mazzarri has not lost in any of the 12 games where he has been in charge of a side against a team managed by Ranieri

• Watford's win was the first time they had beaten a reigning Premier League champion. They had lost four times and drew twice on the other occasions

What they said

Watford manager Walter Mazzarri told BBC Sport: "We got the win and I'm very happy. We played the football that I like my team to play and this time we were good enough to score.

"The way Roberto Pereyra played, not just the goal he scored, he ran the whole game and I am very happy with him.

"It was not easy, we know they are a good team. It was our fault with the penalty, in the last 15 or 20 minutes Leicester pressed a lot and we had to concentrate."

Leicester boss Claudio Ranieri told BBC Sport: "I said to my players 'well done' as they tried to do everything. At the beginning we were losing 2-0, but we got back in the match.

"Of course Watford defended very well. We tried to do our best, the second half was intense but we did not created good chances.

"Their two goals made the match. Our performance was good, the spirit was good and I am positive. When you play with this spirit, I'm positive."

What's next?

Leicester are in action again on Tuesday as they host Club Brugge in the Champions League. A win for the Foxes will take them into the last 16 of the competition.

They next play in the Premier League on Saturday, 26 November when they entertain Middlesbrough, with Watford in action the following day with a home league game against Stoke.