Wales suffered a World Cup blow as Serbia struck late on at the Cardiff City Stadium to earn a 1-1 draw.
Gareth Bale's 26th Wales goal -- which moved him to within two of Ian Rush's national record -- looked like handing Chris Coleman's side three precious points in Group D.
But Newcastle striker Aleksandar Mitrovic headed an equaliser five minutes from time, which Wales goalkeeper Wayne Hennessey was unable to claw out after the ball had struck the post.
That was particularly cruel on a Wales side who had seen Bale hit the woodwork at the other end only 50 seconds earlier.
Mitrovic's goal could really hurt Wales in the final World Cup reckoning as the Dragons now trail new group leaders Republic of Ireland by four points.
Wales' next World Cup test is in Dublin at the end of March and that game now takes on huge significance.
It is a game Wales simply can not lose if they are to enjoy a successful journey on the road to Russia.
Serbia had lost top place at kick off following the Republic's win in Austria, but their two-point lead over Wales was backed up by a psychological advantage from a win in 2014 World Cup qualifying.
Wales had lost those games 6-1 and 3-0 with manager Chris Coleman admitting he is still haunted by the nightmare in Novi Sad which was one of the nation's heaviest ever defeats.
Serbia's 3-0 win in Cardiff in September 2013 was also the last time that Wales had lost a competitive game on home soil, and there was an edge to the Welsh opening which Coleman felt had been missing in the October draws against Austria and Georgia.
Coleman went against type by playing a flat back four rather than his usual three-man central defence, with Bale given a licence to roam but primarily utilised down the right flank
Bale had an early shooting opportunity which cleared the bar and the returning Aaron Ramsey saw his shot blocked by Luka Milivojevic, but Serbia's noted counter-attacking threat soon began to surface.
Filip Kostic spied an opening until James Chester intervened, but from the resulting corner Branislav Ivanovic's header required the presence of Neil Taylor on the far post for the deadlock to remain.
But Wales were ahead after 31 minutes when Hal Robson-Kanu muscled Matija Nastasic off the ball and laid it in to Bale's path in a central position.
Bale shifted it onto his favoured left foot and drilled it low past Vladimir Stojkovic, with the Serbia stopper feeling he might have done more to keep the effort out.
It was Bale's fourth goal of this World Cup campaign.
Wales almost doubled their lead moments later when Aaron Ramsey fed Bale down the left and his cross was diverted just wide by Robson-Kanu at the far post.
The temperature was rising at the Cardiff City Stadium and Taylor caught Dusan Tadic with a high foot which left the Southampton player with a bloodied nose.
Bale's dissent over an earlier decision earned him a caution from Spanish referee Alberto Undiano Mallenco, and Wales held onto their lead courtesy of a fine Hennessey stop from Nemanja Matic's powerful strike.
The second half started with a trademark Bale free kick which dipped and swerved from 30 yards, and Stojkovic just did enough to keep the ball out.
Tadic was playing with cotton wool up his nostrils after his earlier injury but he was still pulling Serbian strings as the visitors tried to find a way back into the game.
Wales had only threatened sporadically in the second half but Bale almost won it when he strode on to Ramsey's pass and struck the foot of a post.
And the sting in the tail came less than a minute later as Mitrovic showed his strength to hold off James Chester and divert his header past Hennessey.