Despite having occupied a top-two spot since round 10, the Warriors are in danger of missing out on a home semi-final should they fail to beat Ulster, while a bonus-point victory may also be required.

The hosts are boosted by the return of captain Al Kellock in what could be the lock's final ever appearance at Scotstoun, in front of a packed-out crowd of 10,000.

Sean Lamont returns from injury to replace Niko Matawalu on the left wing, with the Fijian international moving back to his preferred scrum-half slot to partner Finn Russell, who comes in for Duncan Weir at fly-half.

Dougie Hall and Rossouw de Klerk come into the front row, while Josh Strauss moves to blindside flanker and Adam Ashe takes up the No.8 jersey.

And Townsend admits his side will be drawing on the experience of being beaten finalists last season to help them overcome their title rivals this weekend.

"The stats show that no away team has won a semi-final in the GUINNESS PRO12 so it is important and a great reward for our supporters as well to come back for another game," he said.

"I don't know if we've got the most difficult tie - Ospreys going to Connacht is going to be very difficult.

"But we have a lot of respect for Ulster, they've been in great form and they'll be highly motivated too after not managing to beat Munster last week.

"In theory I will have access to the other scores but you get so wrapped up in your game that I'll probably just refer to them every now and again.

"We've had the experience of being in the semi-final and the final so we've got that knowledge and we're playing pretty well apart from last week.

"I do think it's really competitive this year, there's not much between the top four teams and it can be just about getting momentum at the right time or taking your opportunities."

Ulster head coach Neil Doak has made 12 changes to the side that secured a thrilling late draw against Munster last time out, with only Louis Ludik, Franco van der Merwe and Chris Henry retained.

Yet the Ulstermen have selected a stellar bench, with internationals Rory Best, Tommy Bowe, Ruan Pienaar, Paddy Jackson, Roger Wilson and Iain Henderson all named among the replacements.

And despite the changes, Stuart McCloskey, who will partner debutant Sam Arnold in midfield, insists his side can end the Warriors' home streak to secure a home semi-final of their own.

"We're going over there to win," he said. "We just have to go, try to get the win, and hope the Dragons or Connacht do us a favour.

"I heard a stat the other day that no PRO12 team has ever won an away semi-final. But I think we can go anywhere and win. Anybody can beat anybody on the day and especially as it's a semi-final.

"I'll hopefully have a good game and put the coach under pressure and give him something to think about to maybe put me in there.

"To play in the semi-final would be great no matter who it's against or where it is. Of course it's a massive carrot with the final at the Kingspan Stadium and, if we can come back here, I don't see anyone beating us.

"But it's all about getting there first and what we need to do, and we'll know all about that over the next two games."

Note: This game will also see the HawkEye System in operation again, as part of trials with Sky Sports and World Rugby

At Scotstoun Stadium, 3pm
Live on Sky Sports

Referee: Ian Davies (WRU, 31st competition game)
Assistant Referees: Neil Paterson, Sam Grove-White (both SRU)
Citing Commissioner: Paul Minto (SRU)
TMO: Jim Yuille (SRU)

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