Mesut Ozil is expecting Manchester City's German signings Leroy Sane and Ilkay Gundogan to intensify the challenge facing Arsenal in the Premier League.
The Germany international said he was pleased to see his friends and compatriots Sane and Gundogan join City from Schalke and Borussia Dortmund respectively, and claimed the influx of new players and managers across the Premier League would make his fourth season in England his toughest yet.
Sane and Gundogan's arrivals in Manchester have coincided with those of Paul Pogba and Zlatan Ibrahimovic at Old Trafford, while City manager Pep Guardiola has also added John Stones and Nolito to his squad.
Ozil - who has finished fourth, third and second in the Premier League since arriving at Arsenal in 2013 - told Spox.com: "Manchester United and Manchester City are among the biggest clubs in England and will be very strong in the coming season.
"I am particularly pleased at City, where two of my team-mates from the German team, Leroy Sane and Ilkay Gundogan, are playing. They bring both a great quality and the Premier League will be even better for it.
"All the clubs have invested heavily, not only on world-class players, but also on world-class coaches that have been brought into the league. All teams have improved and I am looking forward to measuring myself against the best players in the world and being able to prove myself against them."
Ozil played in 35 of Arsenal's league games last season - the most since joining the club - and he has shaken off the accusations of being a £42.5million flop that dogged him in the early part of his time in north London.
But the 27-year-old claimed he was never bothered by the criticism, and has focussed only on the opinion of Arsenal manager Arsene Wenger.
He said: "What the media or other people think about me does not matter, frankly - whether positive or negative. The coach has his image, and his mind, and that's what counts. In addition, I also have my own feelings and I know my power to evaluate myself.
"Ultimately, I work hard every day to be able to call my own potential. That worked so well last season, and I am particularly pleased. That is the best reward for the commitment and discipline."