DUSAN TADIC tore Ireland to pieces in the second half, picking up three assists in a 3-2 win.
Ireland will be left wondering what might have been after going ahead thanks to a lovely Alan Browne goal in the first half.
Dušan Vlahović then equalised in the 40th minute thanks to a gorgeous assist from Tadic, which proved to be a theme of the night.
Ireland hardly laid a glove on Serbia in the second half, and eventually Serbia's pressure paid off in the form of a gorgeous chip from Aleksandar Mitrović.
Poor Mark Travers was caught off his line by the Fulham striker, and he won't want to see a replay of the goal anytime soon.
Both sides had potential penalty shouts waved away by the referee, and with no VAR in place, there was not much made of either appeal.
Mitrović then made it three with a powerful header, again assisted by the brilliant Dusan Tadic, who really proved to be the difference on the night.
And potentially more worryingly going forward, Aaron Connolly went off injured in the 67th minute, and was replaced by Shane Long.
Long went on to do quite well and set up a late goal for fellow substitute James Collins, but it proved to only be a consolation.
Stephen Kenny's men will have to dust themselves off ahead a game against Luxembourg on Saturday night.
Elsewhere in the group, Portugal unsurprisingly defeated Azerbaijan 1-0 thanks to an own goal.