Hamilton won promotion back to Division Two with a deserved 2-0 victory at Montrose.
But the visitors had endured an early scare after just eight minutes when a looping effort from Ian Joy struck their crossbar.
The Accies recovered and opened the scoring after 25 minutes when David McFarlane picked up a loose ball and hammered a 25-yard drive high into the net.
And they extended that lead after 54 minutes when Ross McLaren was on hand to score after goalkeeper Gary McGlynn had blocked a shot from Paul Gaughan.
Montrose missed a golden chance to reduce the deficit after 70 minutes when Andy Hutcheon was brought down by goalkeeper Graham Potter and Jonathan Mitchell shot wide from the resulting penalty.
With main rivals Cowdenbeath and Brechin playing each other on the final day of the season, Hamilton are assured of at least a top two spot and progression to the Second Division.