Airdrieonians won for the first time in five meetings with Alloa as Calum Gallagher and Adam Frizzell secured a 2-1 success.
Gallagher opened the scoring in the 12th minute at the second attempt after his initial header was saved.
Frizzell fired home from the edge of the box after good build-up play to double the lead five minutes after half-time.
Rico Quitongo’s goal-line clearance denied Alloa’s Mark Durnan an immediate response but Conor Sammon halved the deficit just after the hour mark.
The former Kilmarnock, Derby and Falkirk striker headed another good chance straight at keeper Max Currie and Jon Robertson shot wide as the hosts held on.