Fiorentina coach Paulo Sousa has said he is mentally tired as he comes towards the end of his first season as a Serie A boss.
The Viola topped the table earlier this season and, with Juventus and Napoli both making poor starts to the campaign, were being tipped to win the Scudetto.
But they have won just one of their last nine games, and Sousa told Mediaset: "There's such a fierce competition among coaches here in Italy, and all sides are difficult to beat.
"This city and this club need to improve and to grow, but I've invested so much energy and I have reached the stage where I'm tired.
"This is a defect of mine which I must improve. I need to manage myself better so that I always have the energy I need for my team. Games like these [the 2-1 defeat to Juventus at the weekend] take everything out of you."
Sousa, who won the Hungarian league with Videoton in 2012, the Israeli top flight with Maccabi Tel-Aviv in 2014 and the Swiss league with Basel last season, said he would learn from his first year in Italian football management.
"We have always shown that we can compete at the highest level, but if you want to take the next step and win things you've got to raise the bar," the Portuguese added.
"I and all the lads have given it everything we have got, but we have got to improve. We can hold our own with everybody, but obviously it's hard to do that for an entire season.
"But our objective is to have this same attitude in every game to be able to compete with Juventus."
Meanwhile, honorary president Andrea Della Valle dismissed reports of a breakdown in the club's relationship with the coach.
"There's no fracture between us and Sousa," he said, according to Fiorentina News.
"Let's instead focus on securing a place in Europe and trying to get as many points as we can in the games that remain.
"We have a major objective, to defend fifth place, then we will have a good look at things when the season's over. We should be proud of this team."