Dumbarton struck twice in the first half to overcome 10-man Falkirk 2-1.
The visitors took the lead after six minutes when Garry Fleming turned Jordan Kirkpatrick's low drive past a helpless Michael McGovern in the Falkirk net.
Mitchel Megginson doubled Dumbarton's lead after 23 minutes, meeting Paul McGinn's cross with a well-placed right-footed effort.
Falkirk pulled one back after 39 minutes thanks to a stunning strike from Philip Roberts. The forward cut in from the left-hand side before unleashing a long-range effort that flew past Jamie Ewings into the top-left corner.
The home side had a strong appeal for a penalty turned down 10 minutes into the second half when Chris Turner brought Blair Alston down in the box.
Alston almost punished the Sons again two minutes later, letting fly with a right-footed effort that rattled off the crossbar.
Roberts was sent off in injury time for Falkirk after picking up a second caution for kicking the ball away.