The Ospreys still believe they can avoid leaving Europe next season – whatever the outcome of the UK referendum.

Wales’ most successful region have never fallen out of Europe’s premier tournament, but unless they beat Ulster at home on Saturday in the final round of the regular Guinness Pro12 season, they will not be in the European Champions Cup for 2016-17.

It doesn’t stop there, either. They also need for their bitter rivals the Scarlets to do them a favour by winning away at Munster.

But the Ospreys are heading into the Liberty clash in good heart on the back of three successive bonus-point wins, responding strongly to their derby defeat to the Scarlets, which appeared to end all hopes of a top-six spot.

“After the Scarlets game we saw that we had four fixtures ahead that we would need 20 points from. We have got to 15, so why not give it a chance to go for another five and see what comes,” said backs coach Gruff Rees.

“With respect to Dragons, Treviso and Blues to a lesser extent, it’s a different challenge this weekend. Ulster are the second best defensive side in the league.

“We can’t just be gung-ho with parts of our attack. We are going to have to be smart where we eke out our tries and create some pressure. We’ve scored some great open-play tries but we need to get them from different sources as well.

“Ulster will have one eye on Thomond Park as well because they may have to chase tries as well. The dynamic may have to change within the match but we’ll learn more in the first quarter and go from there.

“It would be disappointing if we didn’t do it, but we’ve battled those demons in the last couple of months and faced up to the possibility that could be reality — and faced up to them with a fight and a positive mindset about how we are trying to play.

“I think if you are not flourishing year-on-year in this league, we’d be worried. We’ll manage the summer and next season regardless of the competition with our players’ best interests in mind and our drive to be the best we can be from next season onwards.”

For the Ospreys to secure sixth place, a win against Ulster is essential, while the Scarlets must defeat Munster, with the Ospreys securing four more match points than the Munstermen.

If Munster secure two or more match points, they are guaranteed sixth spot regardless of what happens elsewhere. For their part, the Scarlets simply require one more match point than Ulster to extend their season, with Ulster obviously targeting the semi-finals themselves.

The third team still in the hunt for sixth place is Edinburgh, one point and one place behind the Ospreys, who host the Blues at Murrayfield. The Scottish side can still pip both the Ospreys and Munster if they secure a bonus point win, the Ospreys fail to pick up five match points and Munster finish the day pointless.