Manchester City have underachieved since their 2008 takeover by Sheikh Mansour, says Jose Mourinho.
City won the FA Cup in 2011 and the Premier League title in 2012 but have only got beyond the Champions League group stage once in three attempts.
"They won one title, won a couple of cups," said Chelsea boss Mourinho ahead of their away game at City on Monday.
"The team is fantastic, the squad is fantastic and normally they [should] win more titles."
Mansour, the senior member of the Abu Dhabi ruling family, has spent more than £700m on transfer fees since buying City, allowing the club to recruit world-class players such as David Silva and Yaya Toure.
They were knocked out of the Champions League in the group stage in 2011-12 and 2012-13, but will face Barcelona in the first knockout round this season, with the first leg at home on 18 February.
In three seasons in the Europa League since 2008, they have never progressed past the quarter-finals.
"In Europe they didn't do well, or close to doing well," added Mourinho. "Speaking objectively, they did very bad in the Champions League in previous seasons, also in the Europa League.
Mourinho also rejected Tim Sherwood's claim that Manchester City are the best team on the planet and insists the Premier League leaders have been "lucky" this season.
Spurs manager Sherwood said City were peerless after his side were thrashed 5-1 at home by Manuel Pellegrini's men. But Mourinho said City have been assisted by referees.
"The reality is they have many crucial decisions in their favour," he said.
Mourinho cited numerous examples of what he saw as City's good fortune in recent weeks, including disallowed goals against them by Liverpool's Raheem Sterling,Newcastle's Cheick Tiote and Tottenham's Michael Dawson.
"They are lucky," he added. "The referees, they try to do their best and sometimes they make mistakes and normally during the season the mistakes are split between teams.
"In their case, they have everything in their favour."
City manager Pellegrini refused to rise to Mourinho's bait, preferring to keep the focus on the importance of the match.
"It is not me against Mourinho, or him against me," he said.
"On Monday it is Manchester City against Chelsea, both teams are fighting for the title. Nothing more.
"For both teams it is a game of six points. With Arsenal we are the three involved in the fight for the title, and also Liverpool and Everton, so every game we play against all those teams is a game for six points."
City will be without prolific striker Sergio Aguero, who faces a month on the sidelines after pulling up with a hamstring injury against Tottenham.
Aguero, who has scored 26 goals this season, had only recently returned from a calf problem when he stayed on for the full 90 minutes against Watford in the FA Cup on 25 January, scoring a hat-trick to keep City in the competition.
But Pellegrini denied that the cup outing had contributed to the Argentine's latest problem and insisted they could cope without him.
"It was not a mistake because for us the most important thing is to win the match that we have to play.
"Maybe in that game he played 10 or 15 minutes more than planned but I don't think that had a direct relation with his injury.
"He's a very important player for us because he's a top player.
"There's no doubt about that, but we've just played one month or five weeks without him and we've continued winning and we've continued scoring goals."
City have won all 11 of their Premier League home games this season, averaging almost four goals per game.
Chelsea defender Gary Cahill says his team face a huge challenge against a side that have scored 115 times in all competitions.
"They're banging goals in left, right and centre. It's going to be really tough," he said. "I suppose it's the ultimate test."