Rafael Benitez takes charge of Chelsea for the first time on Sunday with a big decision to make over whether to restore striker Fernando Torres to the starting line-up against Premier League leader Manchester City.
The Spain striker was dropped by Roberto Di Matteo for Tuesday's Champions League loss to Juventus, which proved to be the last straw for owner Roman Abramovich before firing the Italian and hiring Benitez.
Torres has scored just four Premier League goals this season, scant return for the 50 million pounds Chelsea spent in January 2011 to prize him from Benitez's former club, Liverpool.
But Benitez should know how to get the best out of Torres, having brought his fellow countryman to Liverpool from Atletico Madrid in 2007 and then seeing him score 33 goals in 46 matches in his first season.
And Benitez, who was fired by Liverpool in 2010, is confident that Torres can rediscover his form with Chelsea.
"He is a top-class player and, with his attitude, he will do it," Benitez said. "I know how good he can be ... he's one of the important players in this team, and I'll try and improve him."
Benitez doesn't plan any radical changes to the team he has inherited from Di Matteo.
"Before I have used 4-4-2, 4-3-3, 5-3-2, but because this is the shape Chelsea have been using until now, I think at this moment this is the best shape for the team," Benitez said. "You cannot change too many things, we have to do the things they were doing well, carry on with these things and then change the other little things."
Although Chelsea is on a four-game run without a win in the league, Manchester City manager Roberto Mancini is expecting the third-place team to be galvanised by Benitez's arrival.
"Usually when one team changes a manager the game after for the opponents is very difficult," Mancini said. "For us, I think it is more difficult. Chelsea is a good team with Di Matteo and will be a good team for Benitez. They have good players.
"Until three games ago they played fantastic football and were on the top."
Now, though, City tops the Premier League, with a one-point lead over Manchester United.
United on Saturday is also facing a team which has just fired its manager, although Queens Park Rangers was still to appoint Mark Hughes' successor - having begun talks with Harry Redknapp.
Hughes was dismissed after less than a year, with QPR bottom of the league without a win despite a massive overhaul of the squad in the summer transfer window.
"It's probably a lesson to everyone that changing a team and bringing 11 new players in to the Premier League is not easy," Ferguson said. "But I am surprised they've only got four points.
"I didn't expect them to immediately set a blazing trail or be up at the top of the league or anything like that with 11 new players to bed in, but they've only four points and of course that creates its own headlines."
Also Saturday, fourth-place West Bromwich is at Sunderland and fifth-place Everton hosts Norwich. The other games are: Stoke v Fulham, Wigan v Reading and Aston Villa v Arsenal.
On Sunday, Liverpool manager Brendan Rodgers makes his first return to former club Swansea since leaving the Welsh club in the offseason, while Southampton hosts Newcastle and Tottenham is at home to West Ham.