Last updated on .From the section Man City

Pep Guardiola will equal his longest run without a win as a manager - five matches - if his team fail to beat Southampton on Sunday

Pep Guardiola says he will never change his tactical philosophy despite his Manchester City side suffering a 4-0 defeat at former club Barcelona.

Lionel Messi scored a hat-trick against an exposed City defence and goalkeeper Claudio Bravo was sent off for handling outside his box after a misplaced pass.

"There will be no change. Until the last day of my career as a coach I will try to play from our keeper," he said.

Barca lead Champions League Group C with nine points, five ahead of City.

City were already a goal down in the early stages of the second half when Bravo intercepted a through ball, but then gifted possession to Luis Suarez.

The Chilean goalkeeper, who was stranded outside his area, then deliberately handled the Uruguayan's lob towards goal.

"Sometimes there are mistakes and sometimes you have to kick the ball out, but most of the time, when we play good, it starts from there," added Guardiola.

"Of course he knows what he did, but he has a lot of experience and he's one of best goalkeepers in last 10 years, so I don't have doubts about him."

Former Barca keeper Bravo replaced England's Joe Hart as City's number one in the summer

'The game was open when we had 11'

City have not won any of their past four matches but are top of the Premier League and Guardiola won his first 10 games after he took charge in the summer.

The 45-year-old said his side needed more time to be capable of challenging at Barcelona's level.

"We lost the game 4-0, but we are a new club, we are getting to know each other," he said. "We are a club that for 35 years was not in Europe.

"We came here and played with huge personality but it is always difficult to play Barcelona with 11. With 10 the game was over. Until then the game was open."

'City will struggle to win the Champions League'

Former Manchester United and Everton defender Phil Neville said City were not of the same standard as their Spanish rivals.

"City are nowhere near where Guardiola wants them to be," Champions League winner Neville told BBC Radio 5 live.

"Barcelona are only at 80% of where they can be and this shows City are nowhere near them and will probably struggle to win the Champions League this year."

This was the first time the Premier League leaders had conceded four times in the competition, which represented another miserable return to the Nou Camp for Guardiola.

The Catalan won 14 trophies during his four-year tenure as Barca boss, but he has now twice lost heavily to the Spaniards - the other occasion a 3-0 first-leg semi-final defeat with Bayern Munich in May 2015.

Neville's City player ratings (out of 10) Claudio Bravo: The red card cost his team dearly in the second half 4 Pablo Zabaleta: The defender had a tough evening against Neymar and then limped off injured 6 Nicolas Otamendi: It was difficult night for the centre-back up against the movement of Suarez 6 John Stones: Played well for 60 minutes but got frustrated in the last half hour 6 Aleksandar Kolarov: The full-back was steady on the left against Messi 6 Ilkay Gundogan: The German midfielder made a horrendous mistake for the third goal 5 Fernandinho: The Brazilian made a poor mistake for the first goal when he slipped 5 David Silva: The playmaker had a poor night and misplaced too many passes 6 Nolito: The winger was sacrificed when Bravo was sent off. He caused problems for Mascherano in the second half 6 Raheem Sterling: The winger showed glimpses of brilliance and frustration - he didn't get the service he wanted 6 Kevin de Bruyne: The Belgian was the best player for City - he made fantastic runs 8

Are City closer to Barca than they were?

Pep Guardiola was part of the Barcelona team that won the European Cup at Wembley in 1992. He lifted the trophy twice more as a manager at the Nou Camp

City are accustomed to losing to the five-time European champions. They were beaten in all four of their encounters under Guardiola's predecessor, Manuel Pellegrini, including elimination in the last 16 in 2014 and 2015.

The Premier League leaders were marginally the better side in the first half this time - they made only 30 fewer passes than the hosts and had an almost identical passing accuracy (78.4% to Barcelona's 78.6%).

Had defender John Stones headed home David Silva's free-kick to level before the break, the second half might have unfolded differently.

Neville, who won the competition with Manchester United in 1999, added: "City have still got a way to go. Their players were giving the ball away, not following the instructions of Guardiola.

"There are better teams in Europe than Barcelona this season but they were far better than Manchester City."

Pep's City slow after fast start 24 Sep: Swansea 1-3 Manchester City Four points clear at the top of the Premier League 28 Sep: Celtic 3-3 Manchester City City slip off Barca's pace in the Champions League 2 Oct: Tottenham 2-0 Manchester City Premier League lead down to one point 15 Oct: Manchester City 1-1 Everton Premier League lead down to goal difference 19 Oct: Barcelona 4-0 Manchester City Five points off Barca in Group C

'Guardiola needs to change personnel'

Former Manchester United midfielder Roy Keane on ITV: external-link "Manchester City's approach was very brave, but very stupid."

Former Manchester City defender Richard Dunne on BT Sport: external-link "I don't trust Bravo with the ball at his feet."

Former Manchester United defender Rio Ferdinand on BT Sport: external-link "The personnel aren't up to executing Guardiola's ideas - he needs to change personnel"

Phil Neville on BBC Radio 5 live In Short: "Bravo has got massive massive amounts of ability, Pep will want him to continue doing what he's doing, taking risks."

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