Chelsea boss Maurizio Sarri insists spending money is no guarantee for success as he focuses on changing the mentality at Stamford Bridge, rather than potential new recruits for January.
After a strong start under the Italian the Blues have triumphed in only one of their last four Premier League outings, a worrying dip in form prior to hosting table-topping Manchester City on Saturday.
Pep Guardiola endured a similarly sticky spell in his first season in England, yet heavy investment in the squad prior to the 2017-18 campaign helped them canter to the title.
Sarri is not against Chelsea signing a player who adds something to the team, yet feels a complete overhaul will not necessarily close the gap to City.
"Not always. We need to work, we need to improve, we need to understand very well the style of playing," he told the media.
"We need to change the mentality, not because the old mentality was bad. But it's not suitable with the new way of playing.
"Then, after all this, maybe you do need one player. But the market is really very important when you understand that you need only one player in one position for changing the team.
"But you cannot think that you can buy 11 new players without problems. If you do, the problems will be the same.
"You have to create a new mentality and a new style of playing. We need to improve. We need to arrive at 95 per cent of our potential, then we can get the last five per cent with a new player. With a new player, not 11 new players."
When asked to specify which position he was looking to strengthen, Sarri replied: "I don't know. At the end of the day, I can tell you the position.
"But before we need to know the improvement of every player in the team. And then, maybe, you are able to know the right position for changing the team."
Sarri spoke to Guardiola back in June and revealed how the Spaniard suggested his rival should look to only develop a select group of players at Chelsea, those he feels have a long-term future at the club.
"He told me the first season in England is really very difficult," the former Napoli boss said.
"For him, it's impossible to improve the first season 20 players. He told me, in the first season, you have to work only on 14 players otherwise you are in trouble. You need too much time to improve all the squad. In England, it's really very difficult."