The Ospreys moved to the top of the Magners League after being forced to battle for the points by Connacht at the Liberty Stadium.
Dan Biggar scored 14 points, including his first ever try for the region, while Gareth Owen also touched down.
There was a late reshuffle in the front row for the Ospreys, with Richard Hibbard, still feeling the effects of knee ligament damage suffered in last month's Heineken Cup win over Leicester Tigers, dropping out to be replaced by Ed Shervington. Marc Breeze joined the replacements.
The return of Mike Phillips on the bench following four months on the sidelines due to a ligament injury picked up against Clermont Auvergne in October was a welcome sight, while Jerry Collins was also present after a whirlwind visit to the southern hemisphere to attend a family funeral in Samoa, a round-trip via New Zealand that saw him leave Swansea on Wednesday, only returning to the UK earlier today.
After a scrappy start it was the Ospreys who got the first points of the game, Biggar popping over a penalty from the 10m line in the 9th minute after he had been the victim of a high tackle by Robbie Morris as he tried to find a gap in the Connacht line. The visitors almost helped themselves to the first try just a couple of minutes later, loose play from both teams seeing the ball bouncing around in midfield which allowed Sean Cronin to gather and charge forward some 20m. He seemed destined to go over, only for a great last ditch tackle by Biggar to bring him down just short of the line. As the ball was recycled the Ospreys offended, allowing Ian Keatley to level the scores.
Biggar spurned the chance to put his side back in front when his attempt from in front of the posts drifted to the right, but just a minute later the Ospreys did score. Collins, an early replacement for the injured Tom Smith, made the hard yards bringing the ball out of defence and after he was tackled the ball was fed out quickly for fullback Owen to collect on halfway, from where he scythed through the Connacht cover to go all the way for his fourth try of the season. Biggar was again unsuccessful with his kick, the ball striking the upright.
At the halfway point of the first period the Ospreys were grateful to TMO Nigel Whitehouse who ruled out a Connacht try after Jamie Nutbrown's clearing kick from a defensive 5m lineout was charged down by George Naoupu on the line, Nutbrown recovering to hold him up with the assistance of Shervington, preventing the player from grounding. There was another scare when a darting run from Connor O'Loughlin saw the scrum half bursting clear, only a tremendous covering tackle from Owen halting his progress just a few metres from the line, Ray Ofisa knocking on he he tried to collect the offload.
Connacht were enjoying the better of a low-quality affair, and Keatley reduced the deficit to two points with a simple penalty from in front of the posts after the Ospreys Nutbrown was pinged for coming from the side of the ruck.
The Ospreys were finally able to gain some territory as the interval approached, putting together some good phases of rugby, and were duly rewarded with a penalty when Connacht where penalised for not rolling away after the tackle, Biggar slotting it over to make it 11-6 at the break.
HALF TIME: OSPREYS 11 CONNACHT 6
There was a change at the break for the Ospreys, Mike Phillips introduced to the action in place of Nutbrown.
The home side were the first on the board after the restart, Biggar's penalty extending his team's lead, and it was the fly-half who grabbed the game's second try just minutes later. The ball was worked wide by the Ospreys from a scrum, Gareth Owen making a great run up the flank before offloading cheekily behind his back for the supporting Biggar who went over in the corner for his first ever try for the region. His conversion attempt was unsuccessful, leaving the score at 19-6.
The Ospreys were reduced to 14 men with 55 minutes gone when Ian Evans was yellow carded for
Connacht made their extra man count almost instantly, showing good patience to work the Ospreys, dragging in players into the ruck before the ball was spread wide for Mike McCarthy. His offload found Cronin in support, who burst through some poor Ospreys defence to score, Keatley missing the conversion. The visiting scrum half made no mistake with his next attempt, a simple penalty from just outside the 22 after Craig Mitchell had offended, bringing his team back to within five points with a quarter of the game remaining.
With the Ospreys having conceded eight points while he was off, Evans made a welcome return to the action, and he was joined on the field by Cai Griffiths who replaced Mitchell.
Biggar was off target with a penalty attempt from 42 metres that would have helped to settle Ospreys nerves as the game approached the closing stages, before Connacht were then reduced to 14 when Gavin Duffy was sent to the sin bin after being caught offside.
Connacht cut the deficit to just two points through a late Keatley penalty, which meant that the Ospreys had to endure a nervy final few minutes, but the home side were able to hold on for an important, if unconvincing win.