West Bromwich Albion sacked manager Tony Pulis on Monday after a miserable run of form that has seen the Chinese-owned club slump to 17th in the Premier League table.
Pulis has won just two of his past 21 league games following Saturday's 4-0 defeat by Chelsea and West Brom sit one place above the relegation zone after an 11-game winless run in all competitions.
"These decisions are never taken lightly, but always in the interests of the club," chairman John Williams said on West Brom's official website.
"We are in a results business and over the back end of last season and this season to date, ours have been very disappointing.
"We would like to place on record our appreciation of Tony's contribution and hard work during a period of transition for the club which included a change of ownership.
"We wish him well in his future endeavours."
Assistant head coach Gary Megson has agreed to take charge of first-team affairs until further notice.
Owner Guochuan Lai watched the Chelsea defeat after flying over from China for a pre-arranged trip and is now tasked with finding a new manager, with Aberdeen boss Derek McInnes - a former West Brom captain - linked to the post.
Pulis, 59, replaced Alan Irvine when the Baggies were a point above the relegation zone in January 2015, eventually leading them to 13th.
They finished 14th in 2015-16 and came 10th last season, but failed to win any of their final nine matches.
In a statement released by the League Managers Association, which represents managers in England, Pulis defended his record at The Hawthorns.
"Over the last three seasons we have achieved a great deal and I am proud to have managed West Bromwich Albion," he said.
"My remit was to develop the squad and ensure we delivered results which would in turn improve the club's financial position.
"We have achieved this year on year and I am pleased to have played a part in the club's growth.
"Our final league position in the last three seasons has represented the accomplishment of our targets as a club; sustaining our status in the Premier League and delivering stability, throughout the club's transition of ownership."
Pulis, who boasts a proud record of never being relegated as a manager, has previously been in charge at Crystal Palace.
He also had two stints at Stoke City, where he reached the FA Cup final and qualified for Europe during his second spell at the club.
The number of top-flight sackings was already at a five-season high even before the Welshman's exit, with four up to November 20 compared with the next highest mark of three by the same stage in 2015-16.
The other managers fired so far this season are Frank de Boer (Crystal Palace), Craig Shakespeare (Leicester City), Ronald Koeman (Everton) and Slaven Bilic (West Ham United).