Guardiola wants City to become 'believers'

City came into the third round encounter at the London Stadium having won four of their last five Premier League games, but a seven-point deficit to Chelsea at the top of the table and some inconsistent recent displays had opened the door to criticism.

The City boss had cut a terse figure following their Premier League victory over Burnley on Monday, giving a tetchy post-match interview having grimly hinted at his own retirement in the build-up.

A comprehensive win at the London Stadium, however, the heaviest home defeat ever inflicted on West Ham in the competition, gave him cause for optimism and he called on his players to take inspiration from the way they got the job done.

"Finally, we were able to keep the ball more than the last games, where it was almost impossible, so we played much, much better in that sense. We create more chances when that happens and we concede few and of course it helps us a lot," he told the BBC.

"Always it is important to win away, it's not easy at West Ham in the cup.

"Hopefully it can help us to make our players believers that they are good enough to play every game. They have to believe they are able to compete wherever."

City were irresistible as they tore into West Ham, taking the lead from the penalty spot through Yaya Toure, who has seemingly been reinstalled as a pivotal presence in the City squad having been frozen out at the start of the campaign.

An own goal from Havard Nordtveit and an effort from David Silva gave the visitors a 3-0 halftime lead while Sergio Aguero and John Stones, who netted his first goal for the club, wrapped up victory in the second half.

"I should have scored in previous games," Stones said. It's nice to get one in a special cup."

"I thought we moved the ball well," the England defender added. "We changed our system and played with a diamond. It worked really well.

"To get a clean sheet was good -- we haven't had too many."

(Reporting by Toby Davis, editing by Pritha Sarkar)