Manchester City and Pep Guardiola are working on the margins to make Erling Haaland even better after his blistering start to life in the Premier League.

Haaland joined City on a five-year deal formalised in June after the club activated a €60 million (£51.2m) release clause in his deal with Borussia Dortmund.

The Norway striker has quickly illustrated why he has developed a reputation as one of the most fearsome strikers in world football.

Haaland has found the net six times in his first four Premier League games, scoring a hat-trick to help City come back from two goals down to beat Crystal Palace 4-2 on Saturday.

Yet ahead of Wednesday's meeting with Nottingham Forest, Guardiola indicated he believes Haaland can reach an even higher level.

He told a press conference: "We're delighted. Hopefully he feels good being here.

"We only had one month of competition. We still have margins to improve [for him] to be a better player and we're working on that."

With City facing a packed fixture list as the Champions League, which they begin with a trip to Sevilla, starting next week, talk has already turned as to when Guardiola may rest Haaland.

When he does so, Guardiola is confident Julian Alvarez, whom City signed in January from River Plate, will be ready to fill the void.

"When Erling doesn't play, we play Julian," Guardiola added. "Almost sure. We are all really impressed for his pace, sense of goal, his work ethic, for many things.

"Every session [he] leaves everything. Impact in pre-season, now plays minutes. Involved in two goals the last game, always the sense to be involved in the right areas.

"When he drops he has the quality to play. Everyone is talking about Erling, but he is exceptional."

While Haaland completed City's comeback against Palace, Bernardo Silva was the one to start it.

Silva has been the subject of interest from Barcelona, while Paris Saint-Germain are also said to be keen on the Portgual international.

Reports have suggested Barcelona have given up on signing Silva in this transfer window, and Guardiola reiterated how highly he thinks of the former Monaco star.

"With Bernardo I said many times how important he is for us," said Guardiola. "Just one, two days finally the window will be over and everyone will be focused on what we have to do."