Chelsea manager Antonio Conte has warned Manchester City to "pay great respect" to Southampton if they follow through with their interest in defender Virgil van Dijk.
The Citizens are seen as the frontrunners to land the Netherlands international, who was close to swapping the south coast for Liverpool during the summer window.
Conte believes that a move to the Etihad Stadium will devalue the competitiveness of the Premier League, however, as runaway leaders City - 14 points better off than Chelsea - will simply continue getting stronger and stronger.
"Every team, every club, must pay great attention," he told reporters. "If a club like Manchester City takes all the best players, it will be very difficult for us to fight. Not only in England but in Europe.
"If they can do this, it is right for them to do this. We must pay great respect. When you have this opportunity to go in the market to spend a lot of money, I think it is right to do this.
"You must obviously be very good to spend your money in this way - sometimes you can spend a lot of money in a bad way. You must be clever to understand the positions, the roles you have to improve. In this case you must be very good."
Van Dijk, also linked with Chelsea and Arsenal in the past, is reportedly still valued at around £70m by Southampton.
