Ospreys head coach Steve Tandy is urging his troops to rediscover their rhythm against Munster or risk waving goodbye to their GUINNESS PRO12 play-off hopes. The Welsh side have won just one of their five GUINNESS PRO12 matches in 2015, a run that has seen them slip to fifth in the table. However, they are unbeaten at the Liberty Stadium in the league in over a year and will be looking to get back to winning ways this Saturday as Munster come to town. While Ospreys are slipping down the table the Munstermen are going in the opposite direction and their 22-10 victory over Glasgow last time out was their fourth game unbeaten as they climbed to the summit. But despite the hard task facing his side, Tandy insists it is now or never as Ospreys bid to keep their play-off dreams alive. "This is a huge game for us having dropped out of the play-off spots last week,” he said. “Munster are at the top of the table now and are a quality outfit, so we know that we are going to have to be at our best if we are going to get the performance level needed to ensure we stay in touch after this weekend. "At the risk of repeating myself and stating the obvious, this is an absolutely crucial period as it always is, a month that can shape how the table looks come the end of the season. “We've had some disappointments the last few games but I think week on week there have been clear improvements, to the extent that we should have had more from the Leinster match and were all disappointed at the final week. "That disappointment has set the tone in training, there was a focus last week that we've carried through to this week, and preparation has been good. “The players understand that this is a game where they have to front up, be they the youngsters in the squad or the older, more experienced heads who have a duty to provide the leadership we need on and off the field. "If we can get the performance level right on Saturday, ensure that we are on top of the factors we can control, then we'll be where we want to be. If the outcome of that is the win, then we'll be in a healthy position for the end of season run-in.” Howells welcomes back Justin Tipuric and the Wales international leads the side out against Munster as he takes the No. 7 jersey from James King. King will line up at six as Joe Bearman missing out with a groin injury, while Tevita Cavubati is struggling with a shoulder problem so Lloyd Peers comes into the second row. And the only change among the backs following the 9-9 draw with Leinster sees Tom Habberfield replace Martin Roberts at scrum-half. Meanwhile, Munster head coach Anthony Foley has made three changes to the starting XV that defeated Glasgow Warriors, with Dave Kilcoyne coming in at loosehead, Dave O’Callaghan returning at six and Felix Jones pitching up on the right wing. Donnacha Ryan is also included in a matchday squad for the first time this season as Munster bid to continue their happy travels to Wales, having lost just once in their last seven visits. BJ Botha is once again in the No.3 shirt and he is hoping for more of the same against Ospreys. "Obviously there are a few guys missing at this time of year, but we still want to keep our scrum as strong as ever and I think we did that. We have good consistency at set-piece,” Botha said. "It's great that we now have a number of good combinations in front rows, especially after us being depleted due to injury earlier in the season. “We're now getting a lot of these guys back and it's great for competition and the strength in depth. There's still a long season ahead with guys coming in and out of the squad for internationals or injury, so it's good to know that we have a number of different combinations that work. "It's also good for these combinations to get more and more game time and that's why you'll see some rotation, it's all part of working ahead creating that strength in depth." At Liberty Stadium, 2.40pm. Live on Sky Sports Referee: Marius Mitrea (FIR, 37th competition game) Assistant Referees: Sean Brickell, Simon Rees (both WRU) Citing Commissioner: Ray Wilton (WRU) TMO: Simon McDowell (IRFU)