Ulster and Connacht have both been drawn away to Premiership opposition in the last 16 of the Challenge Cup.
Ulster will take on a familiar opponent in the form of three-time champions Harlequins, whom they beat twice in last season's Heineken Champions Cup pool stage.
And should Ulster come through that game, they'll be away again in the last eight against either the Dragons or Northampton.
Connacht have been handed a tough draw, away to the Leicester Tigers, who were guaranteed to play at Welford Road following their 100 percent record earlier in the competition.
However, Andy Friend's side would have home advantage in the quarter finals if they can come through that test, with the winner set to face either the Ospreys of Newcastle Falcons.
Exact kickoff times are yet to be confirmed, with the round of 16 to be played on the weekend of April 4/5/6, while the quarter finals will take place the following weekend.
Challenge Cup round of 16
Dragons v Northampton Saints
Ospreys v Newcastle Falcons
London Irish v Cardiff Blues
Harlequins v Ulster
Benetton v Agen
Zebre v Bath
Leicester Tigers v Connacht
Montpellier v Glasgow Warriors
Challenge Cup quarter finals
Montpellier or Glasgow Warriors v Benetton or Agen
Dragons or Northampton Saints v Harlequins or Ulster
Zebre or Cardiff Blues v London Irish or Cardiff Blues
Leicester Tigers or Connacht v Ospreys or Newcastle Falcons
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