Newtongrange Star deservedly collected all three points but only after sub Jordan Cropley scored their long-awaited second goal with his first touch to ensure the victory.
Lee Currie added their third for good measure.
Early exchanges at New Victoria Park were even as Nitten, beaten 3-0 at relegation-threatened St Andrews earlier in the season, sought revenge.
But early Star chances went begging as Kris Renton was denied by Saints goal keeper Darren Clarkson’s outstretched leg, a David Morris header went narrowly wide and another Renton effort just cleared the bar.
At the other end, a speculative shot by Saints’ Ryan McInnes drifted inches over the bar.
In 23 minutes, a free kick by United’s Ricky Patrick swept across the face of the home goal but there were no takers to finish it off.
Craig Thomson then raced forward and unleashed a cracking drive which only just cleared the far post with Clarkson beaten.
Finally, in the 34th minute, Newtongrange broke the deadlock when a Thomson free kick from the right was met by Kevin Motion, whose header found the United net via a deflection off Liam Rowland.
Skipper Blair Tolmie dealt with United’s reply from the first corner of the afternoon as a strong Star defence kept a tidy clean sheet for the day.
Within a minute of the restart, Motion’s header from a Thomson corner clipped the crossbar.
A second goal was proving elusive and another Renton effort almost caught Clarkson off his line, but the keeper scrambled back to hold the ball on the goalline.
St Andrews had a brief spell of pressure as they chased an equaliser but after manager Alan Miller had made substitutions going into the last 20 minutes, the second Star goal eventually arrived. Thomson’s fine right-wing run and cross from the byeline found Cropley who scored with a close-in finish to to give Nitten the two-goal cushion they needed in 73 minutes.
Saints replied with two unsuccessful attempts at goal before an 80th-minute cross by Thomson was parried by Clarkson but only to Currie who dispatched the ball into the net for Star’s third goal, deservedly sealing all three points for the hosts.