Fourth-placed Ayr and Caley Thistle in fifth both have two games to make up before the league splits for a final three games, but the 5-2 victory for United lift them nine points ahead of their Highland rivals.
Clare Docherty opened the scoring with a free kick and Lyndsey Whiteside added to Ayr’s tally within the opening ten minutes of kick off. Docherty grabbed a second either side of a brace from Emma Dawson, with Iona MacArthur and Rhea Hossack netting for the hosts.
Elsewhere in the Championship, leaders Livingston remain eight points ahead at the top after beating Morton 3-0 in Port Glasgow thanks to a double from Shannon Mulligan and a header from Jess Murphy from a corner.
Second-placed Renfrew kept up with an impressive 4-1 victory in Dundee against Dryburgh Athletic and Rossvale beat Hutchison Vale 3-0 in Edinburgh.
In the Women’s League One, Champions FC Edinburgh brushed aside rivals Edinburgh Caledonia 7-1 in the Edinburgh derby, while the race for the second promotion slot heated up after Stenhousemuir came from behind to beat Westdyke 2-2 and leapfrog them into third place.
Falkirk ended St Mirren’s promotion hopes with a 4-0 victory to remain second in the table.
Giffnock Soccer Centre denied BSC Glasgow the point they needed to lift out of the relegation zone with a spirited comeback to win 3-2, while Airdrie ran out convincing 6-0 winners against Dundee West.
In the regional Biffa SWFL, Bonnyrigg Rose moved level on points with Linlithgow Rose in EAST after beating them 2-0, WEST leaders Harmony Row won comfortably 6-0 at home to Annan Athletic, Inverurie Locos beat Stonehaven 1-0 in NORTH and in SOUTH, Kilwinning brushed aside Nithsdale Wanderers 6-0.