Substitute Oumar Niasse scored two goals as Hull City secured a potentially crucial victory over fellow Premier League strugglers Swansea. The 26-year-old, on loan from Everton, had only been on the pitch six minutes when he latched on to Abel Hernandez''s pass and slotted past Swans keeper Lukasz Fabianski. The Senegal forward''s second came just nine minutes later, with a close-range finish from fellow substitute Ahmed Elmohamady''s cross. It was a nervy finish at the KCOM Stadium, as Swansea defender Alfie Mawson pulled one back in injury time. The Swans had enjoyed the better chances earlier in the game, but struggled without top scorer Fernando Llorente, who was forced off with an injury at the end of the first half. The Tigers remain in the bottom three, one point from safety, but moved to within three points of Swansea, who remain in 16th.