Saints started brightly and gave as good as they got for the first ten minutes without creating a real chance on goal.
They were punished shortly afterwards when Ronald broke through to round Lee Wilson and gave Rose an early lead.
Things got worse for United when a Rose free kick was judged by referee Craven to have been handled by a Saints player in the area.
Coyne calmly hit the spot kick to Lee Wilson’s left for a 2-0 lead.
United were forced to make a change when Dylan Honeyman took a bad knock and was replaced by Stark.
A Rose free kick on the 36 minute mark was headed over the top from good position at back post.
Just two minutes later another Rose free kick was hit well from the stand side and Thom arrived unmarked to head well into the roof of the net.
Four minutes from half time a bad tackle by Rose’s Ovenstone saw him sent off.
Saints tried hard with the extra man advantage but Rose managed to cope and, at times, looked as if they could score again.
Falconer had a go from outside the area on the hour mark but it was well wide of the target.
A corner ten minutes later reached Quinn at back post but his header was too high.
Another Falconer effort saw McKinven, the Rose keeper, scramble back to cover the chip but the effort was just a few inches too high.
A free kick for Saints ten minutes from time came to nothing before the second of two excellent crosses by Stark with was met and headed well by substitute Davidson into the bottom corner of the net for a goal which Saints more than deserved.
That was Saints’ last away game of the season and the four home games left are as follows Saturday, March 16, Broxburn Athletic; March 23 Preston Athletic; March 30 Ormiston; no game 6 April; April 13 Linlithgow Rose.
United: L Wilson, Blaney, Cunningham, S McDonald, M Fleming, McManus, Honeyman (Stark(29), Penman, J Wilson (Rendall 54), Falconer, Quinn (Davidson(77).
Subs: Hutchison, Moran, D Fleming, A McDonald.