Post Roll Video Ad Play While The Main Video Is Playing?

I want the Post Roll video to ONLY start playing after the previous video has played. The problem is that when the Post Roll video is set to auto play is start playing but I want it to ONLY play after the previuos video has completely ended.

if((typeof jQuery == “undefined”) || !window.jQuery )
var script = document.createElement(“script”);
script.type = “text/javascript”;
script.src = “”;
var acanceltext = “Cancel”;
var startNextVideo,moveToNext,nextPlayUrl;

$(document).ready(function() { jwplayer().onComplete( function(){
startNextVideo(); }); }); $(document).ready(function() {
jwplayer().onPlay( function(){
}); jwplayer().stop();
$(‘.bigadclose’).click(function(){ $(‘.pre-roll-ad’).addClass(‘hide’).remove(‘.pre-roll-ad’); jwplayer().play(true); });
jwplayer().onComplete( function(){
$(‘.bigadclose’).click(function(){ jwplayer().play(true); });