Ospreys 33-26 Munster
Ospreys (23) 33
Tries: Storey, Tiueti, A Williams. Cons: Henson 3. Pens: Henson 4.
Munster (12) 26
Tries: Staunton 2, Wallace, Mullins. Cons: O'Sullivan, Staunton 2.
Gavin Henson's kicking masterclass proved the difference as the Ospreys overcame Munster's spirited challenge at St Helens.
The Irish province outscored their hosts by four tries to three, but 18 points from Henson's boot ensured a narrow home victory.
The Ospreys opened up an 18-point lead with tries from James Storey, Dave Tiueti and Andy Williams.
But tries from Mike Mullins and Jeremy Staunton in the final quarter brought Munster to within a converted try of a superb comeback.
Hopes of an open and entertaining encounter were raised immediately from the kick-off as both side looked to make the most of the perfect playing conditions.
And with just 10 minutes on the clock, two converted tries had already been recorded on the scoreboard.
Munster were the first to strike when full-back Staunton ran in unopposed after a period of sustained pressure had stretched the Ospreys defence across the width of the field.
But the home side only needed six minutes to get back level. Fly-half Shaun Connor sent a high cross field kick to the Munster right corner and centre Storey collected Tiueti's knock-down to score.
Tiueti was denied a try soon afterwards when he was held up by Munster scrum-half Eoin Reddan over the tryline; but the powerful winger was celebrating a minute later.
A superb sweeping move along the backline from left to right created the overlap for the Tongan to score his side's second try.
Full-back Henson added a second conversion and then a second penalty on the half hour mark opened up a healthy 20-7 Ospreys lead.
Ospreys back Gavin Henson finished with 18 points
But back came the Irish visitors with a try form flanker David Wallace.
Left winger Mossie Lawler put the home defence on the back foot with a surge down the left wing, and after moving the ball across field, Wallace was on hand to dive over in the right corner.
A third Henson penalty brought the half to an end with the Ospreys content with a 23-12 lead.
That advantage was extended to 18 points seven minutes after the break when scrum-half Andy Williams scored his side's third converted try.
The summer recruit from Bath, returning to his roots, showed impressive predatory instincts to pinch the ball from the base of a Munster scrum and race away to score under the posts.
Munster's mobile forwards had the edge over their counterparts all evening, and a series of surging runs wrestled the impetus back the Irishmen's way.
A solid scrum deep in Ospreys territory set up perfect attacking options for the backs, and centre Mullins found a clear passage through the home defence to score under the posts.
Staunton's conversion brought Munster back within 11 points and set-up a tense final 15 minutes.
Henson settled some home nerves by maintaining his perfect kicking record with a fourth penalty ten minutes from time.
But again Munster hit back as a deft midfield move sent Staunton over for their fourth try.
The full-back converted his own try to bring Munster to within seven points, but desperate Ospreys defence in seven minutes of injury time kept the visitors at bay.
Ospreys: Gavin Henson; Dave Tiueti, James Storey, Scott Gibbs (capt), Elvis Seveali'l; Shaun Connor, Andy Williams; Paul James, Barry Williams, Andrew Millward, Andy Newman, Luke Tait, Gavin Thomas, James Bater, Nathan Bonner-Evans.
Replacements: Gareth Morris, Adrian Durston, Ricky Richards, Chris Wells, Steve Tandy, Lyndon Bateman, Cai Griffiths.
Munster: J Staunton; S Payne, M Mullins, J Jones-Hughes, M Lawlor; C O'Sullivan, E Reddan; S Kerr, J Flannery, M Cahill, E Halvey, D Pusey, D Leamy, D Wallace, J Williams.
Replacements: F Roche, J Danaher, T Hogan, C McMahon, S Keogh, M Prendergast, M McPhail, D Crotty.
Referee: Tony Rowlands (Treorchy)