Three unanswered second half tries from Bath condemned the Ospreys to pre-season defeat on Friday night.
A try from Ryan Bevington had helped the Ospreys go in at half-time with a slender two-point lead but the hosts were in control for long spells in the second period.
There were two changes to the starting XV named on Thursday afternoon. Full back Richard Fussell withdrawing through illness which allowed Ross Jones the chance to stake a pre-season claim for the number 15 shirt, youngster Sam Davies coming onto the bench, while Morgan Allen swapped places with Dan Baker to start the game.
The late summer sunshine gave way to autumn drizzle ahead of kick-off, a sure sign that the rugby season proper is almost here.
Bath had an early chance to open the scoring after Tito Tebaldi has strayed the wrong side at a ruck on the Ospreys 22 and George Ford gratefully accepted the three points, slotting over a simple kick.
Just a couple of minutes later though it was all square, Biggar with an equally straightforward kick from a little further out after a Bath offside.
The hosts then looked dangerous as they moved the ball left to right across field after a scrum close to the touchline, Kyle Eastmond halted just a metre a short as he went for the line, ignoring Semesa Rokoduguni on his outside.
It was Bath who were enjoying the better of the early exchanges and only resolute defence on the Ospreys line prevented the home team from grabbing the opening try on 10 minutes, the Bath pack rumbling ominously towards the tryline from a 5m lineout before knocking on over the line.
The Ospreys were in trouble at the resulting scrum, despite having the put-in, Biggar just about getting time to clear after seeing his forwards retreating at a rate of knots.
A Biggar break from just outside his 22 took the Ospreys into the Bath 22 for the first time, Ollie Devoto tidying up the 10’s chip and chase to clear into touch. With the Ospreys having their first attacking platform, Scott Baldwin was unable to find his man at the lineout and Ford sent the ball back into Ospreys territory.
Just past the midway point of the first half an Ospreys offence at the scrum on halfway allowed Ford to put Bath up into the corner, and after another impressive lineout maul sucked in defenders, Peter Stringer spotted the space across the other side of the pitch and got the ball moving along the backline. Matt Banahan was hugging the left touchline where he received the ball off Jonathan Joseph to go over in the corner despite the best efforts of Ross Jones.
Ford sent his conversion attempt wide across the face of the uprights, to leave it 8-3 to Bath with 22 minutes gone.
The Ospreys took the lead just after the 30 minute mark after a stunning team try that took them from just outside the edge of their own 22 to underneath the Bath posts.
Biggar was the catalyst, collecting Ford’s clearance out on the right, carrying into the Bath half before offloading to the supporting Sam Lewis. He had Ashley Beck with him, who carried another 10m before slipping it to Tom Grabham who stepped inside the cover before unselfishly passing to Bevington who enjoyed a clear run into the line. Biggar added the extras, giving his team a two-point lead.
Bath were enjoying the upper hand at the set-piece, without really taking advantage of the dominance, as the autumn drizzle turned to rain. As half-time approached, a Bath offence at the breakdown allowed Biggar the chance to go from goal just inside his own half. His effort fell just short, Bath cleared, and ref Luke Pearce blew for half-time.
HALF-TIME: BATH 8 OSPREYS 10
The Ospreys made a number of changes at the break which saw, among others, Ryan Jones and Richard Hibbard introduced to the action, but it was Bath that struck first after the restart.
With a penalty advantage in his favour after the Ospreys had illegally halted a Bath rolling maul, an outrageous show and go from Ford took out two defenders, and number eight Leroy Houston went over to score, Ford’s conversion making it 15-10.
Bath then grabbed a third try just five minutes later through winger Rokoduguni who started the move with a scything run over halfway, cutting through the heart of the Ospreys defence. After the ball was worked through numerous pairs of hands he then popped up on the right to take the final pass off David Wilson. Ford again made no mistake with his kick.
By the hour mark the Ospreys were fielding almost an entirely different team to the one that started the match. Bath were also making multiple changes, with both teams also sending players back into the action having been withdrawn earlier, which meant that there was little rhythm or continuity to the contest.
Anthony Watson’s darting run put Bath on the front foot, bursting through the midfield, but his little dink ahead for Rokoduguni had just too much on it for the winger to get there before it went out of play.
Bath did grab their fourth try on 77 minutes, a series of pick and goes close to the line sucking in defenders to create the inevitable overlap on the right, and it was Devoto who scored the try. Tom Heathcote’s conversion drifted across goal.
That was the end of the scoring as attention now turns to the start of the PRO12 next weekend and a difficult trip to Treviso on Saturday evening.