Nazem Kadri hasn’t scored in April. Seven games thus far this month and no goals, and no goals since his hat trick in Ottawa back on March 30. On the surface, that span qualifies as a slump. In theory, Kadri is facing more intense coverage from desperate teams who are hitting him at every opportunity and taking away his ice. In reality, the Leafs’ top goal scorer this season must break through that wall and prove he’s a legitimate scoring threat under pressure. So when the Leafs face a bounce back game Thursday against the New York Islanders, one of the underlying stories is getting the talented youngster back in the groove. With five games remaining in the regular season, Toronto’s magic number is four — any combination of Leaf wins and Winnipeg losses totaling four points and Toronto is playoff bound. That number can be realized Thursday with the Leafs at home to the Isles and the Jets entertaining Carolina. At the moment, the Leafs are dealing with Kadri’s slump and two others. Clarke MacArthur (12 games) and Matt Frattin (13 games) are struggling to find the back of the net. Phil Kessel has carried the offence the past two weeks, but Toronto’s reputation this season has been built in part on three scoring lines. Right now, the secondary scoring is dry. Leafs coach Randy Carlyle placed Joffrey Lupul back alongside Kadri on Tuesday as Lupul made his return from a 12-day mild concussion layoff. The hope was twofold: that Lupul’s incredible return from his previous arm injury would be repeated; and that the chemistry he had with Kadri would still be there. Neither unfolded in a flat game in Washington. Toronto was outshot for the 11th straight game.