Ospreys head coach Steve Tandy has challenged his players to respond in style following last weekend’s loss to Connacht as they head to high-flying Leinster in the GUINNESS PRO12. The Ospreys’ three-game unbeaten run in the PRO12 ended in Galway last Saturday with their first away defeat in the competition since round six. However, they have been victorious in Ireland this season, winning 21-17 at Munster last month, and Tandy remains convinced his side can spring a surprise on the road. "Clearly we were disappointed about the outcome last weekend in Connacht. We saw the good and bad of a young, developing team over the course of 80 minutes, but there was so much to be proud of as a coach,” he said. “We started sluggishly, gave them a head start and found ourselves playing catch-up, something that's probably the story of our season. “But you have to give credit for the attitude, endeavour, and bloody-mindedness I suppose, in the way that once again they refused to throw the towel in and deserved to bring something home with them. "We are going to need that attitude in buckets on Saturday as we are going to one of the toughest places in European rugby and we know that we have to be at our best from the very first whistle. Give a team like Leinster a head start and there's no way back.” The Ospreys have been forced into a change in the midfield as they confirmed this week that JJ Engelbrecht is likely to be out for up to eight weeks with an ankle ligament injury. Owen Watkins is selected at No.12, while Josh Matavesi shifts from inside centre to outside, while Rhys Webb captains the side in the No.9 jersey and joins Sam Davies in the half-backs. "In terms of our season, last weekend's result doesn't change anything,” added Tandy. “We knew that we would have to probably win all of our remaining games to grab a Champions Cup spot and that is still the same.” Leinster are the only side remaining in the GUINNESS PRO12 with a 100 per cent home winning record this season, while their solitary defeat anywhere in the last ten rounds was 23-13 at Newport Gwent Dragons in January. Leinster's only defeat in their last eight fixtures with Ospreys in all competitions was 25-19 at Liberty Stadium in the GUINNESS PRO12 in April 2014 whilst the Welshmen's most recent victory at the RDS Arena came in the 2012 PRO12 final against Leinster. There are seven changes in total to Leinster’s starting XV that picked up a bonus point away to Zebre last Sunday, with Dominic Ryan in line to win his 100th cap from the bench. Zane Kirchner will start at full back for his 60th cap for the province with Fergus McFadden coming in on the right wing, while skipper Isa Nacewa continues on the left. There are four changes in the pack with a completely new front row of Cian Healy, Sean Cronin and Mike Ross. "We've a very short turnaround. It's important that we manage the bodies so we're in best possible shape," said Leinster head coach Leo Cullen. "Ospreys I'm sure will be disappointed; they were very unlucky with the loss that they had. They had a try disallowed that could have easily won them the game. “They know they have to really perform. Obviously they're really trying to push for the top four themselves, and even the top six as well. “It's fine margins some of these games. We need to make sure we're as best prepared as possible for that." To buy tickets for the GUINNESS PRO12 Grand Final click here. Also follow us on Facebook, join the conversation on Twitter, sign up to our YouTube channel for extensive match highlights and sign up for our newsletter for regular updates on the GUINNESS PRO12. At RDS Arena, 3pm. Live on Sky Sports Referee: Ian Davies (WRU, 43rd competition game) Assistant Referees: Mark Patton, Richard Kerr (both IRFU) Citing Commissioner: Eugene Ryan (IRFU) TMO: Olly Hodges (IRFU)