West Brom sacked head coach Eric Ramsay on Tuesday after their 1-1 draw against Charlton left them just a point above the Championship relegation zone.
Ramsay failed to win any of his eight league games in charge, taking just four points out of 24 available in a reign that lasted just 44 days.
A former Manchester United first-team coach, Ramsay was appointed by West Brom following a two-year spell with MLS side Minnesota United.
Albion are fourth from bottom with 12 games remaining and first-team coach James Morrison will take interim charge for the second time this season, starting with Saturday's trip to relegation rivals Oxford.
In a statement, Albion said: "West Bromwich Albion have parted company with men's first team head coach Eric Ramsay.
"Assistant head coach Dennis Lawrence has also departed The Hawthorns.
"The club would like to place on record its thanks to Eric and Dennis and wishes them well for the future."
Ramsay, 34, had replaced Ryan Mason with Albion 18th in the table and seven points clear of the bottom three, but he has failed to make a meaningful improvement.
Supporters turned against him following a 3-0 defeat at Portsmouth and during Saturday's 2-0 home loss to Coventry, chanting "You're getting sacked in the morning" and "Eric Ramsay, your football is s---."
In his final news conference after the Charlton game, Ramsay admitted the overall picture is "not good enough" and feels his side took "a step backwards."
George Campbell's header ended a 405-minute goal drought in first-half time added on but Lyndon Dykes's 70th-minute equaliser made it 10 without a win for the Baggies.
"We're not talking about this performance in isolation -- we are adding this to multiple draws, not enough wins and not enough getting over the line so it has the feeling of a step backwards," said Ramsay.
"I know what this situation needs at the moment -- it needs wins, it doesn't need draws.
"The number of chances were enough to win the game but it wasn't good enough.
"We are lacking a real spark and quality in front of goal."
Ramsay had been defiant regarding his future and said: "I am not sat here on the back of five losses where the team has not been competitive.
"Over the last four league games, the team has been competitive, it's fighting and I don't feel there's a lack of connection between me and the team."
After several earlier Albion chances, Campbell met Alex Mowatt's inswinging corner to send a downward header beyond Thomas Kaminski in the fourth minute of first-half added time.
Josh Maja stabbed wide, Charlie Taylor and Jayson Molumby headed off target and Isaac Price skied over and Charlton punished them when Dykes latched onto Kayne Ramsay's through pass and kept his cool to slot through Max O'Leary's legs from six yards.
PA contributed to this report.