Right-back Rangel was part of the Swans side who went down 2-1 at Derby on Saturday, leaving City with just one point from a possible nine.
Similar struggles for promotion rivals Cardiff, Norwich, Nottingham Forest and Leeds mean Swans' position has not been hugely threatened, although the R's have moved 10 points clear at the top with nine games remaining.
"We were all gutted and the changing room was very, very sad (after the Derby defeat)," Rangel told City's official website.
"But we said before the game that if we win it wouldn't get us promoted and if we lost we wouldn't be out of the play-offs.
"Our aim a few weeks ago was to catch QPR, but they are now 10 points ahead with nine games to go. It's not impossible but we have to be realistic and get enough points to get into the top two. Once we get a win everything will change.
"There is pressure, but nice pressure that we must try and enjoy. As players we have to keep our cool and look for our fans to make the Liberty a fortress on Saturday (against Nottingham Forest)."
Source: PA
Source: PA