The Baggies will drop down to the Championship after suffering defeat at the hands of the Gunners on Sunday
West Brom have been relegated from the Premier League after a 3-1 defeat to Arsenal on Sunday.
The loss leaves Sam Allardyce's team 10 points away from safety in the English top flight with three games left to play.
West Brom went behind against the Gunners less than 30 minutes into the clash at Emirates Stadium when Emile Smith Rowe struck from close range. Nicolas Pepe doubled the home side's lead in the 35th minute by smashing into the top corner. Matheus Pereira gave the visitors hope in the second half before Willian wrapped up the points with a late free kick.
What was said?
"It's not sunk in yet, but I'm sure I'll wake up tomorrow and realise the situation," Allardyce told BT Sport. "I'm bitterly disappointed we're not still in the fight.
"I'm not saying we would have avoided relegation but we should have been closer, we should have taken it down to the last three games, based on how we performed. The creating of chances has been there but the converting has not.
"We had [enough] time to pull it round. Our real problem was not beating the bottom-six sides when we came up against them. The results against Chelsea, Manchester United and Manchester City should have been bonus points."
West Brom unable to avoid the drop
The Baggies are now four games without a win, having lost two and drawn two as their bid for Premier League safety collapsed.
Allardyce's team still have games against Liverpool, West Ham and Leeds to round off the campaign.
After just one season back in the top flight, they will return to the Championship with Sheffield United, while Fulham look set to follow, having taken just one point from their last six games.
Allardyce's run ends
After 17 seasons in the Premier League, Allardyce has been relegated from the top flight for the first time in his career.
The story of West Brom's season
West Brom's season had a miserable opening as they started with a nine-game winless run, though they did draw 3-3 with Chelsea in September.
Their first victory came against bottom side Sheffield United in late November and the club hoped to turn their campaign around by changing managers, sacking Slaven Bilic in December and putting Allardyce in charge.
Although they drew 1-1 with both Manchester City and Liverpool, they would not pick up their second win until January 16 when they won 3-2 at Wolves.
Since then they have held Manchester United to a 1-1 draw and beaten Chelsea 5-2 in the highlight of their campaign. They have also recorded victories against Brighton and Southampton.