The London club are in the midst of an alarming slump, sixth in the table after four defeats in a row and in serious danger of missing out on Champions League football.

Boos greeted the full-time whistle following Saturday's 1-0 defeat to Manchester United at Stamford Bridge after some supporters staged a street protest against owners BlueCo ahead of kick-off.

Former midfielder Di Matteo, who guided Chelsea to Champions League glory as manager in 2012, said "inconsistency" was understandable given the young age of the squad.

"I think the owner just said it last week. On the weekend he said that they're probably going to look at changing the transfer policy a little bit," Di Matteo said at the launch of the "Hong Kong Football Festival" featuring Manchester City, Chelsea, Inter Milan and Juventus in August.

"I think it's vital. If you want to have a little bit more consistency, if you want to be able to challenge, maybe for the Premier League, you need to have a good balance.

"You need very good, young, talented players, but you also need a little bit of experience within the team."

The 55-year-old Italian, who was a mainstay of the Chelsea team from 1996 to 2002, said allowances needed to be made for under-pressure Rosenior given he only replaced Enzo Maresca in January.

"You take over a team that was built for a different coach, with a different system," he said.

"It's always hard to be able to put your print on the team during mid-season. Everybody expects you to get it going straight away.

He added: "I guess next season we'll be able to see his team make some adjustments to the way the team (plays) or (bring in) the players to play his system."

Chelsea co-owner Behdad Eghbali last week said the club were still behind Rosenior and remained optimistic about long-term success under his management.