Bath's dominance in the latter stages of the first half proved the difference to ensure they headed back over the Severn Bridge with the win, giving Steve Tandy and his coaching team plenty ponder ahead of the first PRO12 game of the season in two weekend's time.

The morning rain had given way to blue skies and bright sunshine by kick off and despite it being just a pre-season game the opening stages were fairly frenetic, possession being turned over a number of times as both teams tried to find the right gear.

Dan Biggar opted to spurn a simple three points from in front of the posts, just 23m out to go for a lineout in the corner just nine minutes in but the Ospreys pack were held up just short as a driving maul edged them close to the line.

It was the Aviva Premiership side who notched up the first points of the day though after Rhys Webb was guilty of not rolling away. Unlike his counterpart, the Bath 10 Sam Vesty opted to go for the sticks - drawing a few boos from the crowd - and he gave his team the lead 18 minutes in.

Strong defence from Tom Isaacs stopped Tom Biggs from finding a way through on the outside, a good tackle halting the bigger man's progress after Bath had moved the ball through the hands.

Ian Gough was then pinged from coming in from the side and Vesty again opted for the points, taking the score to 6-0 just past the halfway mark of the opening period.

At this stage Bath were doing all the attacking and despite some robust defence from the Ospreys, the try eventually came and it was all too easy in the end as the unlikely figure of British Lion Lee Mears skipped through a huge gap in the line to cross for the first try of the afternoon, Vesty adding the extras.

After the frenetic opening the game had become very stop start with little to get a healthy pre-season crowd of more than 6,000 excited, but confusion between Isaacs and Richard Fussell as they both went for a high ball close to the touchline from Vesty's up and under resulted in the loose ball falling in Bath's favour, a Biggs offload giving Dan Hipkiss a simple run-in to stretch his team's lead to 18, Vesty missing the conversion.

HALF-TIME: OSPREYS 0 BATH 18

After a disappointing first 40 the Ospreys wanted a bright start to the second half so they would have been disappointed to go further behind just four minutes after the restart, Olly Barkley with the penalty.

Despite that setback the home team were actually able to enjoy their best spell of the game so far, putting together some good phase play as they looked to reduce the deficit, but still they were unable to unlock a stubborn Bath defence.

The Ospreys first points finally came after an hour after skipper Alun Wyn Jones instructed Biggar to go for goal from the 22m line despite the three try difference.

The home side were rewarded with their first try minutes later and it was a well worked score for wing Tom Grabham, just on from the bench. Fellow replacement Kahn Fotuali'i was the catalyst with his quick tap and go on halfway allowing him to run at the heart of the Bath defence. Justin Tipuric was in support and when he recycled Bath were completely out of shape, with the Ospreys enjoying a five man overlap on the left. It was moved quickly to Grabham on the touchline who showed a fantastic turn of pace to score in the corner, Biggar converting.

Ospreys tails were up and a second quick Fotuali'i tap penalty almost led to a second try for Grabham but the Bridgend youngster couldn't gather Matthew Morgan's pass.

Try as they might though, there was to be no further scoring as Bath held firm for the victory.