For the game at North End, Stevie Campbell was denied the services of central defender Michael O'Byrne after his red-card at Ibrox, so Neil McMechan partnered Phil McGrath in the heart of the defence with Fraser Milligan dropping back to right-back, making up a back four of Mulligan, McGrath, McMechan and Pope.
The four in midfield were Andreoni, Mathieson, McCord and Paterson.
Up front Johnny Russell returned after a long absence through injury to partner Robbie Feeney.
Starting really well, the link up play was excellent producing a prodigious number of crosses into the box. The only complaint was that the Saints keeper wasn't tested enough.
When he was after 25-minutes, he was beaten. Scott Paterson slid the ball into Gordon Pope's path and his speculative strike from 25-yards flew into the top right-hand corner.
Shortly afterwards, Saints had their best and only real chance of the game, hitting the bar as did defender Neil McMechan as he cleared any danger from the rebound. Fortunately, it only clipped the bar on its way to safety.
Although the second half was much more even territorially after the break, United definitely had the better chances.
Fraser Milligan had a goal chalked off ten minutes after the re-start and in the latter stages the Saints goal had three narrow escapes. Robbie Feeney drilled a shot just past after 71 minutes and four minutes later, Robbie played in Johnny Russell, but he fired past the near post.
Three minutes from the end Ryan McCord was through on goal but his attempted lob was wide of the mark and the ball was scrambled clear from the onrushing Fraser Milligan.
Although it was only by the one goal, coach Stevie Campbell felt that it was more comfortable a victory than the scoreline suggests.
He said, "Having pretty well dominated the first half and the better chances after the break, I don't think any one could argue that we didn't deserve to win.
Equally as pleasing was keeping a cleansheet even although Michael Byrne was absent."
Team: Gibson, Milligan, Pope, McGrath, McMechan, Mathieson, Ryan McCord, Andreoni, Feeney (Dow 86), Russell, Paterson. Subs not used: Cannon, Jeffrey, Ross McCord, Travers, Allan.