It was all Clermiston in the opening half and they made their dominance count as they went into the half-time break 4-0 up.
Striker Sam Knight struck a first-half hat-trick for the hosts with their opening three goals, before Aaron McKay tapped in from close range for goal number four.
Bryan Flockhart ensured the theme of the opening half continued into the second period as he made it five, before South pulled a goal back.
That proved to be merely a consolation as Tony Hepburn netted from the penalty spot after Flockhart was brought down. Mark MacKay’s deflected effort wrapped up a good day’s work for Clermiston.
Saturday Premier Division outfit Edinburgh Star edged out Cavalry Park 3-2 in the first round of the Challenge Cup.
Home side Cavalry played some entertaining football in the first half but it was the visitors who stuck first before the break through Jason McGuinness.
Former Cowdenbeath man Lewis Coult doubled their lead when he headed in Scott Ewan’s free-kick, only for Andrew Grant to net for the hosts.
Danny Glancy’s cross was knocked in by a Cavalry defender for Star’s third of the afternoon, but James Burt ensured a nervy finish when he fired in a free-kick.
Sandys cut the gap on Premier Division leaders Tollcross Thistle to three points with a 3-1 win at Meadowbank.
The visitors started on the front foot and opened the scoring from new signing Mikey Oark’s header.
Ten minutes later and it was 2-0 as Scotland amateur internationalist Bob McKenzie laid the ball on a plate for James Hainey to score.
Meadowbank pulled a goal back on the stroke of half-time, but Sandys didn’t allow the home side to fulfil any hopes of a comeback as McKenzie made it three.
Elsewhere, Duddingston Athletic were impressive 6-2 winners away to Gorgie Hearts in Sunday’s Premier Division with James Woodhouse netting a double for the visitors while Joe Randle for his first goal for Duddingston.