A statement said that although the player has made excellent progress in his recovery, some minor issues remain.
Meanwhile, Paddy Wallace will roll back the years when he pulls on the Ulster No 10 jersey for tonight’s clash with Glasgow Warriors at Scotstoun.
Wallace’s move to fly-half is one of 11 changes coach Mark Anscombe has had to make for what could be a defining game in the Pro 12 for the leaders.
All Black John Afoa captains the side for only the second time while there are first starts for Malone’s tough blind-side flanker Conor Joyce and Dublin-born winger Neil Walsh, while forgotten Ireland winger Andrew Trimble finds himself in midfield alongside Stuart Olding. With Lewis Stevenson not released by Ireland, Neil McComb partners Dan Tuohy in the engine room while Ali Birch again wears the No 7 jersey, with Nigel Brady back at hooker.
ULSTER: R Andrew, M Allen, A Trimble, S Olding, N Walsh, P Wallace, R Pienaar; C Black, N Brady, J Afoa, capt, N McComb, D Tuohy, C Joyce, A Birch, R Diack.
Replacements: R Herring, R Lutton, A Warwick, A O’Connor, M McComish, P Marshall, D Cave, C Cochrane.
GLASGOW: P Murchie; T Seymour, M Bennett, A Dunbar, DTH van der Merwe; P Horne, N Matawalu; O Fainga’anuku, P MacArthur, E Kalman, T Swinson, T Ryder, J Strauss, J Barclay, R Wilson (capt).
Replacements: F Brown, L Pettie, G Mountford, N Campbell, J Eddie, S Kennedy, S Wight, G Morrison.