Arbroath won 2-0 at 10-man Inverness to go top of William Hill League One after Stenhousemuir lost 2-1 at Queen of South.
Relegation battlers Caley were up against it after midfielder Robbie Thompson was sent off late in the first half after picking up two yellow cards.
The visitors broke the deadlock in the 52nd minute through Dylan Smith, with substitute Gavin Reilly adding a second in stoppage time to seal a third straight league win.
Arbroath moved a point clear of Stenhousemuir and still have a match in hand.
The Warriors fell behind at Palmerston Park to an early goal from Reece Lyon.
Adam Brooks doubled Queen of South’s lead on the hour and although substitute Corey O’Donnell soon pulled a goal back, there was no late drama.
Alloa lost ground on the top two after a 2-1 home defeat by Montrose, with Kane Hester’s 89th-minute goal securing a late victory.
Bottom-club Dumbarton were thumped 5-1 at home by Annan on another miserable afternoon while it finished goalless between Cove Rangers and Kelty Hearts.
In League Two, Peterhead beat East Fife 1-0 to move level on points with them at the top of the table.
Kieran Shanks’ early goal at the Balmoor Stadium proved enough to give the Blue Toon a crucial win – and still with a match in hand on the Fifers.
Elgin, though, missed the chance to go back to the top after losing 4-2 at home against Stirling.
Adam Brown scored twice late in the first half as the Binos came from behind to lead 3-1 at the break, with Dale Carrick adding a fourth just before the hour.
Russell McLean scored a hat-trick as bottom-club Forfar thumped Bonnyrigg Rose 5-1 at Station Park but it finished goalless between Stranraer and Edinburgh.
Clyde were edged out 3-2 at Spartans, with Cammy Russell getting a brace. The Bully Wee finished with 10 men following a late red card for midfielder Ray Grant.
