The B & I Cup returns this weekend and Munster 'A' head coach Mick O'Driscoll believes that only a win will do against Nottingham at Temple Hill tomorrow (3pm) if they are to qualify.
Munster are second in the Pool 3 but with top side Worcester Warriors hosting Moseley at the same time O'Driscoll knows that his side can ill-afford to slip up.
"It is going to be very, very difficult. We have to beat Nottingham and put ourselves in a position to hopefully beat Worcester the following week and then we will see who comes out on top in the group," he said.
Munster lost 27-23 away against Worcester in Round 2 but their 11-point defeat of Nottingham last time out kept them in contention.
Munster have already defeated Nottingham at Meadow Lane earlier in the campaign but O'Driscoll will be taking nothing for granted. Nottingham are fifth in the English Championship after registering an impressive 27-26 win on the road against fellow Pool 3 side Moseley last weekend.
"The campaign is difficult in that you are playing against a team that is playing Championship rugby week in, week out.
"They will be used to playing together week in, week out. We will have guys coming from playing Ulster Bank rugby, possibly even U-20 rugby, right up to playing senior rugby, so we will have a big mix of players and that can be difficult in trying to gel it together."