David Slattery bagged two second half goals as Kildare strengthened their grip on Division 2 of the Allianz Football League.
The Confey man was brought on at half-time and netted in the 37th and 50th minutes as Kildare moved three points clear of the chasing pack.
Hosts Down finished the game with 13 men when, after using all six subs, defender Darren O'Hagan limped off injured and sub Jerome Johnston was black-carded.
Kildare boss Cian O’Neill’s decision to introduce Slattery was the game-changer, however.
With his first contribution of the game, the Confey clubman finished a flowing move involving Daniel Flynn and Kevin Feely, impressive at midfield all night and scorer of five pointed frees.
And Slattery was on target again 20 minutes from time, on a big night for O’Neill’s men at Páirc Esler.
Kildare took the chance to pile the pressure on chasers Galway and Clare by claiming victory before their promotion rivals play.
For Down, this was a disappointing setback after two wins on the spin, and they’re now looking over their shoulders again, having harboured hopes of drawing level with Kildare at the top before throw-in.
In truth, this was a disappointing contest, particularly in the first half as Kildare played with the aid of a squally breeze.
At half-time, they were 0-04 to 0-03 clear, but the sides had managed just three points from play between them before the break.
Two of those were scored by Barry O’Hagan for Down, before his influence on the game diminished.
Kevin Feely knocked over a couple of vital frees for Kildare and goalkeeper Mark Donnellan opened their account from a ’45, having denied Ryan Johnston with a smart early save.
Slattery’s introduction proved pivotal as he proved the difference in the second half with two classy goals.
The hosts, playing in front of 1700 spectators, were up against it and their task wasn’t made any easier by a black card for sub Alan Davidson, who wasn’t long on the pitch before his dismissal.
Caolan Mooney kicked a couple of lovely second half points but Down would finish the game with 13 men.
With all six subs used, defender O’Hagan limped off before Jerome Johnston, who had replaced Davidson, picked up a black card of his own.
Down: M Cunningham; R McAleenan, B McArdle, D O’Hagan; D O’Hanlon (0-04f), C McGovern, C Mooney (0-02); A Carr, P Turley; K McKernan (0-01), C Maginn, J Murphy; S Millar, B O’Hagan (0-02), R Johnston.
Subs: A Davidson for Johnston (55), N Donnelly for Carr (57), J Johnston (0-01) for Davidson (b/c 63), M Poland for Maginn (66), S Dornan for Millar (69), C Magee for Turley (69).
Kildare: M Donnellan (0-01, 45); M O’Grady, D Hyland, O Lyons (0-01); J Byrne, E Doyle, K Cribbin; K Feely (0-05f), T Moolick (0-01); F Conway, N Kelly, P Cribbin (0-01); C McNally, D Flynn, C Hartley.
Subs: D Slattery (2-00) for McNally (h.t.), F Dowling for Hartley (54), E Callaghan for Slattery (65), E Heavey for Moolick (68), S Ryan for Conway (70), L Healy for Doyle (70+5).
Referee: N Cullen (Fermanagh).