Manchester City manager Pep Guardiola says he is not surprised by a dip in his team's high standards this season despite his efforts to avoid it.
City crashed out of the League Cup against struggling Southampton on Wednesday and trail Arsenal by five points at the top of the Premier League.
After the 2-0 quarter-final defeat at St Mary's, midfielder Ilkay Gundogan blamed a lack of hunger from the league champions.
"What happened didn't surprise me," Guardiola said on the eve of City's visit to Manchester United in the Premier League on Saturday. "I tried to avoid it.
"It happened and hopefully it won't happen again but it's happened because we did four Premier Leagues in five years. Sometimes you have to reset.
"This was our strength as a team in previous seasons but after back-to-back titles two times, this can happen. We were not ready to go there and be ourselves."
City face a huge week in the title race, with their visit to Old Trafford followed by a clash against Tottenham on Thursday. Guardiola said he wants a strong display from his team against their neighbours.
"Of course, it's an important week," added the City boss. "After what happened at Southampton, the last thing I'm worried about is the titles or this kind of thing.
"It's to recover who you are day, week, day, week, day, week, game by game. This is what we have to do. In important games this season, in the important ones, we were there -- in all competitions."
Meanwhile, Erik ten Hag believes Saturday's derby against City will show whether his United side are ready to challenge for the top honours again.
United were beaten handily when the sides last met in October, losing 6-3 at the Etihad having trailed 4-0 at half-time, but since then they have lost only one of 18 fixtures and they go into the game on an eight-game winning streak.
Victory for United would leave them one point behind City in the league and only increase the emphasis on their trip to face league leaders Arsenal on January 22.
Ten Hag said he was not interested in comparing his side to City but he recognises the bar the reigning champions have set.
"Of course if you want to win trophies you have to compete with the best and Manchester City are the best so we look forward to challenging them," he said. "We will see [if there is a gap] tomorrow."
Saturday will be the second match between Ten Hag and Guardiola, the man who was in charge of Bayern Munich when Ten Hag was coaching their reserve team between 2013 and 2015.
Ten Hag said he did not have time to describe everything he had learned from the Catalan during their time together, but he was clearer when asked about the most important thing.
"To be proactive," he said. "Football is about results but you want to do it in a certain way. To be proactive, adventurous, but also to entertain. Top football is about winning but also entertaining the fans. You play football for the fans."