Diack back for Ulster
Luke Marshall (knee) and Dan Tuohy (hip) picked up low grade injuries in their respective games at the weekend. They will continue to be monitored this week but it is hoped that they will be fit for selection.
Stuart Olding (hip flexor) and Kieran Treadwell (ankle) are doubtful for this weekend.
Peter Browne, Alan O'Connor (both concussion), Iain Henderson (shoulder), Rodney Ah You (knee) and Ross Kane (facial laceration) sustained injuries in the game against Exeter and will be unavailable for selection this week.
In addition, Mark Best is ruled out due to a thumb injury sustained while playing for Ulster A versus London Scottish.
Chris Henry, Marcell Coetzee, Louis Ludik, Stuart McCloskey, Peter Nelson, Matthew Rea and Ricky Lutton remain on the current injured list.
