Sam Allardyce says West Brom are "nearly getting to must win" in their relegation battle.
Albion, 19th in the Premier League, are 12 points adrift of safety having played 24 games.
They have led in three of their last four games but not won any of them, including a 2-2 draw with 18th-placed Fulham and a 2-1 loss at rock-bottom Sheffield United.
Allardyce, appointed Baggies boss in December, said ahead of Saturday's trip to 15th-placed Burnley: "Because we have slipped up, certainly in the two big games against Fulham and Sheffield United, we are now nearly getting to must win, and for me, that is a sad place to be in at this stage.
"It was a no lose in the beginning, now it's becoming nearly a must win, and that's got to be one of the challenges we take up on Saturday. We have to be ruthless enough to try to get three points off Burnley."
Allardyce said being ahead against Fulham and Sheffield United and failing to win was "the real knife in the heart for me".
He said of last Sunday's 1-1 home draw against Manchester United, in which West Brom opened the scoring in the second minute through Mbaye Diagne: "I still haven't got over it, because the chances in the second half were really, really good."
Allardyce has also said he feels players should "do more homework".
"I do think they should do more homework themselves," the 66-year-old said.
"I've thought that for a long time, on the basis of what's available to a player now. I think they should do a little bit more when they are not here, and that's not physical – that's mental, that's tactical.
"Because we can stream as much we want or as little as we want down the line for the next game, or the game before, or the basics, or how do we defend corners, how do we defend free-kicks. That means we don't have to spend a lot of time continuing to practice it here, which makes the training more enjoyable.
"I do believe players have a bigger opportunity than ever before to do a little bit more homework when they're not at their football clubs."
Allardyce also gave his thoughts about social media, following the recent spate of cases of abuse being directed towards individuals in football online.
Among the cases was racist abuse suffered by Manchester United's Anthony Martial, including after the game last Sunday, and West Brom's Romaine Sawyers last month.
Allardyce said: "Certainly the youngsters today seem to want to share everything on social media, and with that you get great benefits, but on the dark side, and the really dark side, we are getting lots more depressed young people, and I think this is because of social media more than anything: bullying, abuse, racial abuse, celebrities getting abused.
"So while there's many good things, there's a lot of bad things, where people are finding it very difficult to live with it. I decided very early I wouldn't enter the social media world."
Asked about footballers coming off social media to avoid abuse, Allardyce said: "Its not the only way they'll stop getting abuse, but it will certainly cut it down to a minimum."
Saturday's match at Turf Moor will see a return to refereeing for Mike Dean, who stood down last weekend after receiving death threats online.
