Burnley came from a goal down in the final 10 minutes to move clear of the bottom three in the Premier League with a 2-1 win away to Watford on Saturday that piled pressure on faltering Everton.
Victory at Vicarage Road, which confirmed Norwich's relegation from English football's top flight, meant the Clarets pulled five points clear of the relegation zone, with Everton, long a mainstay of English football's top flight, in the bottom three.
James Tarkowski's own goal handed Watford a lead that held until the 83rd minute when Burnley's Jack Cork headed in an equaliser.
Minutes later, Josh Brownhill's strike completed the turnaround for the visitors as their revival under Mike Jackson continued.
The interim manager replaced Sean Dyche after the long-serving Clarets boss was sacked with eight games of the season remaining and the northwest club four points adrift of safety.
"We are delighted with the result and the second-half performance, first half we were not where we needed to be," Jackson told the BBC.
"We knew at 1-0 the crowd might get a bit edgy and if we stick with it and get more possession we could get a back in the game."
Jackson, who has taken 10 points from his four matches in charge, added: "These games are so emotionally charged with what is at stake, credit to them for finding a way to win the game.
"We just reminded the group who they are, there was a lot of good work before, so for me it is reminding this group who they are and making sure they deliver on the standards they are capable of."
Defeat all but relegated Watford, who are 12 points adrift of safety.
The Hornets must win all of their remaining matches and achieve a sizeable goal-difference swing, while hoping other results go their way, to stay in the Premier League.
Watford assistant manager Ray Lewington said his side had paid for trying to hold on to their early lead.
"Because we have not won in so long there is a massive fear factor," he said. "Footballers try to protect it, they have seen the clock and the last 15-20 minutes they were almost camped on the edge of our own box."
Everton last played in the second tier of English football in 1954 but Burnley's win has added to the growing pressure on the Merseysiders ahead of their match match at home to third-placed Chelsea on Sunday.
Frank Lampard, the Everton boss, will be up against the club where he won several trophies as player only for Chelsea to sack him as a manager during his second season in charge at Stamford Bridge.
Thomas Tuchel, the current Chelsea manager, then used predecessor Lampard's squad to win the Champions League just months after his arrival in west London.