Huw Bennett scored the only try - and Dan Biggar and James Hook kicked the rest of the points - as the Ospreys opened their Magners League campaign with a deserved win at Connacht.
Connacht endured a second-half collapse at the Sportsground, losing new number eight Mike McComish and scrum-half Frank Murphy to the sin-bin in quick succession.
Taking full advantage, the Ospreys scored 10 crucial points during that spell, Biggar booting a penalty and converting replacement hooker Bennett’s score off a line-out maul.
But Connacht, restored to 15 players, showed their battling qualities as they fought back to claim a late bonus point thanks to Ian Keatley’s fourth successful penalty.
The westerners, who finished bottom of the table last season, included three of their new signings from the kick-off – Ireland Sevens internationals McComish and Brian Tuohy and New Zealander Bernie Upton, the former Chiefs and Hurricanes lock.
All Black powerhouse Jerry Collins and former Scarlets full-back Barry Davies made their competitive bows for the Ospreys, with coach Sean Holley also handing scrum-half Mike Phillips an immediate return after his exploits with the Lions.
A late switch saw Jonathan Spratt drafted in as a last-minute replacement for injured centre Andrew Bishop (shoulder).
Connacht had the backing of the wind in the first half. But after an early Keith Matthews break was snuffed out, the Ospreys began to shade possession.
Teenage fly-half Biggar kicked the visitors ahead with a drop goal in the ninth minute.
But Connacht hit back when a push in the line-out allowed Keatley to land his first penalty.
Keatley attacked off the restart, making a surging 28-metre break. He found Niva Ta’auso up in support - and although the move petered out, the Ospreys leaked another penalty which Keatley slotted between the posts.
Biggar kicked his side level at 6-6 four minutes into the second half - and the Welsh outfit turned the screw, dominating possession through their pack.
Keatley hit a post with a penalty chance, and Biggar edged the visitors ahead with his second penalty.
Then with a controversial offside decision against Murphy putting Connacht down to 13 players, the breakthrough try duly arrived.
Ian Gough won possession off a 60th-minute line-out close to the Connacht line, and a powerful drive shunted Bennett over the line. Biggar added the extras for a decisive 16-6 lead.
The Ospreys had chances to build on their lead, but a lone penalty from replacement Hook was all they could muster in the final quarter.
Connacht came back with two more Keatley kicks to earn a point.