Ilkay Gundogan suggests it is "quite normal" for Timo Werner and Kai Havertz to be struggling at Chelsea after moving to the Premier League amid the coronavirus pandemic.

Werner and Havertz were high-profile recruits from the Bundesliga prior to the 2020-21 season as Chelsea looked to turn a team that scraped Champions League football into genuine title contenders.

Other signings, such as Edouard Mendy, Thiago Silva and Ben Chilwell, have quickly had an impact, but the Germany internationals have found life a little more difficult.

Werner did not score in his first three Blues appearances in all competitions but then netted eight times in nine games, before enduring an 11-match goalless run that takes him up to Sunday's meeting with Manchester City.

The former RB Leipzig forward, who has netted with just 10.3 per cent of his 39 Premier League shots, missing eight big chances, lost his place for the first time for the draw with Aston Villa last time out, albeit Chelsea had played Arsenal just two days earlier.

Werner - involved in eight league goals - has still fared better than Havertz, who has had an underwhelming eight attempts and created 10 chances across 14 games, scoring one and assisting another.

The misfiring pair will meet international colleague Gundogan on Sunday in a crunch clash in the top half of the Premier League.

The City midfielder expects the pair to come good, though, pointing to the difficulty of relocating to a new country under the strange conditions of a global health crisis.

"They have two new German players who have tried to adapt as well as possible," Gundogan told Sky Sports.

"In general, I think it's not easy to adapt quickly to the Premier League when you come from a different country, and now with the situation going on, I think it's just even harder.

"So I think it's quite normal that they are struggling a little bit, but they both have incredible talent and I'm sure they will both be able to prove it in this league."

Chelsea, in sixth, and eighth-placed City are level on points ahead of the game at Stamford Bridge, seven points adrift of co-leaders Liverpool and Manchester United.

Frank Lampard's side have won just one of their past five league matches to quell title talk, but Gundogan is still wary of the threat of opponents who have won their past two home games against City.

"Like every year, Chelsea have a great squad with incredible players," Gundogan said.

"They are a great team and they have a really ambitious manager so I feel like they will really challenge us - not just this weekend but also generally in the league.

"They got some really talented, young recruits in the summer, spent a lot of money and got some really good players, so I think they will do well.

"They've done well; of course, they are also a team that struggles like everyone does, but they have a lot of quality and it's going to be a great game."