text: His signing follows the news that the Stags could be without injured striker Alex Fisher for four weeks.
  Oliver, 23, signed his first professional contract with his hometown club Sheffield Wednesday.
  He left the Owls in 2012 and made an immediate impact at Lincoln City, scoring 14 goals in 41 matches, before joining Crewe last summer.
  Oliver could make his debut at York on Saturday.
target: Forward Vadaine Oliver has joined Mansfield Town on an emergency one-month loan from Crewe Alexandra.