Kevin De Bruyne is expected to be Manchester City’s final acquisition of the summer with the manager, Manuel Pellegrini, increasingly confident of prising the 24-year-old from Wolfsburg.

The German club are now open to selling De Bruyne if City meet their valuation. Sources close to the player believe £45m-£48m would be accepted though Wolfsburg are refusing to make clear the preferred price in an attempt to extract the highest fee.

Despite interest from Paris Saint-Germain, City is De Bruyne’s first choice. While the club has yet to lodge a bid, Edin Dzeko’s expected sale to Roma may lead City to put in a formal offer.

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If De Bruyne is bought City will end their transfer business unless an exceptional player becomes available. Pellegrini has so far added to his squad with Raheem Sterling, for £49m, Fabian Delph (£8m), Patrick Roberts (£11m) and Enes Unal (£2m). The latter has been loaned to Genk.

After a disappointing first campaign Eliaquim Mangala, who cost £42m last summer, is conscious of the need to step up this term. “I am focused on the season ahead and I want to play my part to the full,” he told mcfc.co.uk. “I know I need to improve and show my best game every time I play and that’s what I intend to do.”

City travel to West Bromwich Albion on Monday evening for their opening match. “I need to find my match sharpness which is normal for all of us at the stage of the season,” the Frenchman said. “We are in the final week of our preparations and with a game coming up on Monday we know we need to work hard on the training pitch and get our tactics spot-on as well as every other aspect of our game.

“We want to start the season well and West Brom on the first day is not an easy place to go. For a club like Manchester City, it’s not good enough to end up empty-handed – we want to win the title and other trophies and go as far as we can in the Champions League and that’s the mentality we have at the club.”

During pre-season City lost 4-1 to Real Madrid and 4-2 to Stuttgart, Saturday’s final warm-up match ahead of West Brom. “All the games we’ve played have value and are important because they are building up towards our opening games at West Brom,” said Mangala.

“What happened against Madrid and Stuttgart rang one or two alarm bells and maybe showed we have to change something and be aware because we can’t play the way we did in those two games against West Brom or we’ll get punished.

“That’s why they were valuable games for us – but the fact is that it is better to find out in pre-season friendlies than in the Premier League because the results are not as important. It also gives us an idea of the areas we need to work on and improve. Everything is focused on our first game against West Brom and by Monday, we’ll be ready and focused.”