Former Manchester City manager Kevin Keegan was surprised by the timing of Roberto Mancini’s sacking.

Keegan, who managed City between 2001 and 2005, admitted the club had failed to build on the success of winning the Premier League and said that was not entirely Mancini’s fault.

A year to the day that City won a thrilling final-day game against QPR to pip rivals Manchester United to the title, Mancini was told his services were no longer required.

Keegan told BBC Radio 5 Live’s Sportsweek programme: “(It’s) surprising if you look at the length of time, but if you look at what’s happening in football now (it’s) not surprising at all.

“It was a season where they (the club and the manager) didn’t build on the last season. They did not make any progress and, in fact, they took a step backwards.”

Keegan felt City should have gone on to more success after Mancini added the Premier League title to the FA Cup and Community Shield.

“They made a mistake in that they didn’t strengthen the side in the right way having won something. The signings this season have been poor and that’s what cost them.”

Keegan felt claims that falling out with City’s players had cost Mancini his job were a convenient excuse for the club’s owners.

He added: “They (the club’s owners) are looking at reasons to justify sacking someone who 365 days earlier had won something for them.

“They couldn’t turn round and say he hasn’t done a good job, three trophies in three seasons after they hadn’t won anything for so long was fantastic.”

Keegan believes Mancini’s successor – with Malaga coach Manuel Pellegrini the favourite – will be expected to deliver silverware.

“I think he will realise he’s going to a club that has ambition. He’s going to a club that already has a lot of good players,” he said.