Raith remain one point clear at the top of Scottish League One after a 1-1 draw at home to nearest rivals Falkirk.
Veteran striker Steven MacLean, on loan from Hearts, broke the deadlock two minutes into the second half to give the hosts the lead – his second goal in three games.
It was the 22nd goal of the season for McManus, who was available again having missed Saturday's 3-2 defeat at Clyde through suspension.
Dumbarton made it three wins on the bounce with a 2-0 home win over Forfar.
Ross Forbes put the Pars in front in the 33rd minute before Jai Quitongo's first goal for the club wrapped up the points with 21 minutes remaining.
It was a fourth game without a win for Forfar, who have netted just eight goals away from home this term.
Clyde boosted their chances of avoiding being dragged into the relegation play-off places with a 2-1 win at home to Montrose.
Ally Love opened the scoring in the 12th minute before Ray Grant – his first goal of the season – doubled their advantage six minutes into the second half.
Blair Lyons' 11th of the campaign and fourth in five matches reduced the deficit but the visitors could not muster an equaliser.