Pep Guardiola has challenged Kyle Walker to prove Gareth Southgate wrong after the England manager left him out of his national squad for the second time this season.

The Manchester City full-back has fallen behind Liverpool's Trent Alexander-Arnold and Kieran Trippier, now at Atletico Madrid, in Southgate's pecking order ahead of the Euro 2020 qualifiers against the Czech Republic and Bulgaria.

With Manchester United's Aaron Wan-Bissaka also in contention, it may be that Walker will not add to the 48 caps he has won for his country.

At the same time, the City manager placed further pressure on Walker by spending £60 million ($74m) in the summer transfer window on young Portuguese defender Joao Cancelo, whom Guardiola believes is now ready to challenge for a regular first-team start.

But Guardiola, whose side host Wolves on Sunday, believes the 29-year-old Walker is currently exhibiting form good enough to win over Southgate and retain his place with the champions.

"Kyle, it is a big challenge for him to show the manager from England how good he is," Guardiola said at his pre-match press conference on Friday.

"Our life in sports is about challenge, about duels, targets, and he has one in front of him in every single game to show how good he is to come back into the team.

"He came as an incredible, outstanding player and still is an outstanding player. Physicality, strong, fast, and we try to help him to be better since we were together."

Southgate has indicated that Walker is too defensive minded for his preferred system with England.

"We ask him many times don't attack from wide but from inside, yeah but as player he can do everything," said the City manager. 

"The opinion of Gareth, I am not here to (question). He made the selection, he had a huge selection of players to select, he decided the last two times and Kyle respects it, I respect it.

"Gareth does what he does for the best of the national team in England. It's a big challenge for Kyle to show how him good he is. Not because he's not in the national team will my opinion change, and neither will Gareth's. So, he remains an incredible full-back."

Walker's Cancelo threat

To compound Walker's concerns, Cancelo, after a slow start to his City career following a summer move from Juventus, is now looking capable of supplanting him in Guardiola's first team.

"With the ball we don't have doubts, without the ball he (Cancelo) starts to understand what we want and he did it quite well in the games he has played," said the City boss.

"Kyle doesn't have doubts about that. Last season it happened in one or two games -- Danilo played a few games last season and he reacted incredibly well, so we cannot play 11 months with one player.

"We survived two seasons with no left full-backs, so we need this player, this position, to make competition for Kyle and let him rest and maybe when Joao plays in a good level, take his position, that's what it is."

City will be without Kevin De Bruyne as he recovers from a groin injury but the Belgian, along with defender John Stones, should be available for a first-team return after the upcoming international break.

De Bruyne has scored two goals and assisted another nine in an incredible start to the Premier League season, while the only game he has not started was City's one defeat so far at Norwich.

Feature image courtesy: AFP/ Anthony Devlin