Steve Cooper admits Swansea have a "mammoth task" to win automatic promotion from the Sky Bet Championship after QPR claimed a late victory at the Liberty Stadium.
Lyndon Dykes drove home an 89th-minute winner to leave Swansea nine points behind second-placed Watford with three games to play.
The Hornets, who had earlier won 1-0 at promoted Norwich, also have a superior goal difference of 14 over Swansea, and the Welsh club must now surely focus on cementing their place in the play-offs.
"Technically we are not (out of the running) but it's a mammoth task now and we obviously haven't helped ourselves tonight," head coach Cooper said after Swansea had slid to a third home defeat in four games.
"We have just got to make sure we win the next game.
"There are three left and unless we win games nothing can happen."
"It's been a psychological test for a while and it still is. We have to prepare and then deliver."
Swansea sharply felt the loss of 15-goal top scorer Andre Ayew, who was missing with a hamstring injury suffered on Saturday.
Ayew should return before the end of the season and his return would appear crucial after Swansea failed to punish QPR during the early exchanges.
"We are disappointed because of the number of chances we created in the first half which we didn't take and it cost us," Cooper said.
"I would have expected to have taken one. We didn't manage to create as much in second half, because turned the ball over and lacked composure.
"That's not like us. We conceded territory and that's how they took advantage with the goal at the end.
"We tried to make changes and alter the shape but we couldn't affect the game."
QPR's fourth win in six games took them into eighth place and manager Mark Warburton admitted his players had been motivated by talk of them having nothing to play for in the closing weeks of the campaign.
Warburton said: "I hate this mid-table mediocrity nonsense. It's your responsibility to hunt down every point when you pull the shirt on.
"I heard it said there were two sides at Middlesbrough (on Saturday) with nothing to play for.
"I thought that was massively disrespectful. You're a professional player. How can you have nothing to play for?
"Young players trying to impress for next season, players trying to earn new contracts.
"I get angry about that. If we can finish in the top 10 on one of the smaller budgets we've done really well."