In-form Iain Russell helped maintain Queen of the South's Scottish Championship play-off push with the only goal against bottom-of-the-table Alloa.Russell nudged Queens ahead in the 41st minute, tapping in Derek Lyle's cross at the back post - his fourth goal in five league games.Jake Pickard, Russell and Mark Millar had earlier been denied by Alloa keeper Scott Gallacher.After the break, Michael Duffy rattled the crossbar for Alloa and was then foiled by Queens stopper Robbie Thomson, with substitute Ryan Conroy having his free-kick tipped on to the post by Gallacher.