It was Ella Toone - playing her 50th game for the Reds - who got the ball rolling from a first-half penalty, while Alessia Russo grabbed her maiden goal for the Reds in the second period, before substitute Jane Ross scored our final strike in injury-time.
United supporters also got a first opportunity to see new signings Lucy Staniforth, Tobin Heath and Christen Press in action, all of whom were introduced as second-half substitutions.
It was a frenetic start to proceedings at Leigh Sports Village, but the best chances in the opening five minutes came from corners at either end of the field, both of which flashed dangerously across the box but went unmet by an attacking player.