Frank Lampard's position as Chelsea manager is under fresh scrutiny following defeat at Leicester on Tuesday evening.
Lampard is the 12th different manager to serve under owner Roman Abramovich.
Here, the PA news agency looks at each of their records at the club – with the figures making unpleasant reading for the incumbent.
Claudio Ranieri (Sep 2000-May 2004)
Won 107, drew 46, lost 46 (Win percentage 53.8, points per game 1.84)
The Italian was at the helm when Abramovich arrived at Stamford Bridge in June 2003. After heavy spending he led Chelsea to a second-place finish in the Premier League and the Champions League semi-finals but was sacked at the end of the season. He went on to win a memorable Premier League title with Leicester in 2016.
Jose Mourinho (Jun 2004-Sep 2007, Jun 2013-Dec 2015)
First spell: Won 124, drew 40, lost 21
Win percentage 67.0, points per game 2.23
Second spell: Won 80, drew 29, lost 27
Win percentage 58.8, points per game 1.98
(Overall win percentage 63.6, points per game 2.12)
The Portuguese established himself as a Chelsea hero, winning back-to-back league titles, one FA Cup and two League Cups in his first spell. His departure only a month into his fourth season by 'mutual consent' was unexpected but he returned in 2013. A third league title and a League Cup followed but a dismal start to the 2015-16 season saw him leave the club for a second time.
Avram Grant (Sep 2007-May 2008)
Won 36, drew 13, lost 5 (Win percentage 66.7, points per game 2.24)
Appointed technical director in 2007, the Israeli controversially succeeded Mourinho. He lasted only one season, finishing second and losing the Champions League final to Manchester United, but has the best win overall percentage and points per game of any of Abramovich's managers.
Luiz Felipe Scolari (Jul 2008-Feb 2009)
Won 20, drew 11, lost 5 (Win percentage 55.6, points per game 1.97)
Brazilian Scolari was the first World Cup-winning coach to manage in the Premier League but a poor run of form saw him sacked before the end of his first season.
Guus Hiddink (Feb-May 2009, Dec 2015-May 2016)
First spell: Won 16, drew 5, lost 1
Win percentage 72.7, points per game 2.41
Second spell: Won 10, drew 11, lost 6
Win percentage 37.0, points per game 1.52
(Overall win percentage 53.1, points per game 1.92)
Hiddink succeeded Scolari until the end of the season and combined his duties with his post as Russia manager. He lost only one match and won the FA Cup but could not be persuaded to stay. He returned with less success after Mourinho's second departure.
Carlo Ancelotti – Jul 2009-May 2011
Won 67, drew 20, lost 22 (Win percentage 61.5, points per game 2.03)
Led Chelsea to a first ever league and FA Cup double, with his side becoming the first to score more than 100 Premier League goals in one campaign, but was sacked hours after finishing second in his second season.
Andre Villas-Boas (Jun 2011-Mar 2012)
Won 19, drew 11, lost 10 (Win percentage 47.5, points per game 1.75)
Hailed prematurely as the new Mourinho, Villas-Boas' tenure at Stamford Bridge was not a happy one. After talk of a player revolt, he was sacked with Chelsea outside the Champions League places.
Roberto Di Matteo (Mar-Nov 2012)
Won 24, drew 9, lost 9 (Win percentage 57.1, points per game 1.93)
The former Chelsea midfielder had been Villas-Boas' assistant and was made interim manager until the end of the season. Champions League and FA Cup wins earned him a permanent contract but the following season did not go nearly as well and he was sacked.
Rafael Benitez (Nov 2012-May 2013)
Won 28, drew 10, lost 10 (Win percentage 58.3, points per game 1.96)
The club's latest interim manager was unpopular with Chelsea fans because of his Liverpool past but won the Europa League and led the team to a third-place finish in the league.
Antonio Conte (Jul 2016-Jul 2018)
Won 69, drew 17, lost 20 (Win percentage 65.1, points per game 2.11)
The Italian enjoyed a terrific debut season, with dominant Chelsea winning the league by seven points, but entered his second under a cloud after appearing to criticise the club's transfer policy. The Blues finished fifth, missing out on a Champions League place, and even an FA Cup win could not save Conte.
Maurizio Sarri (Jul 2018-Jun 2019)
Won 39, drew 13, lost 11 (Win percentage 61.9, points per game 2.06)
The club won Sarri's first five league games at the helm and were unbeaten in 12, but a relative dip early in the new year saw Sarri's tactics questioned. They recovered to finish third, reached the League Cup final and won the Europa League but still moved on.
Frank Lampard (Jul 2019 to date)
Won 43, drawn 17, lost 23 (Win percentage 51.8, points per game 1.76)
Operating under a transfer embargo in his first season, Lampard successfully integrated a number of youth players en route to a fourth-placed finish and an FA Cup final. They lie eighth in the league this season after two wins in their last eight.
