The Welsh side looked on course for the win, armed with a healthy 18-7 interval lead, but scores from Andrew Farley and John O'Sullivan in the last half hour saw the Irish province repeat their victory over the Ospreys at St Helen's.

Ospreys full-back Gavin Henson opened the scoring with a 26-metre penalty, backed by a strong breeze, after two minutes but lax defending allowed Connacht the stronger field position throughout the first 20 minutes.

The home side struck for the game's first try on 14 minutes when Mark McHugh picked up a bouncing ball on the run to round Stefan Terblanche's tackle for the touchdown.

Former Ireland A international McHugh kicked the extras for a 7-3 lead.

South African Terblanche was shuffled into touch by Connacht's Matt Mostyn on 22 minutes when a quick Ospreys reply looked on, but Henson reduced the deficit to a single point with his second penalty.

Ospreys closed out the first half in front, however, thanks to a Steve Tandy try set up by a flat pass from his back-row colleague James Bater in the 26th minute.

Henson missed the conversion to the left, as did McHugh with a 35th-minute penalty but a long Shaun Connor pass saw Bater over with two minutes remaining as the Ospreys took an 18-7 lead into the second half.

Henson added his third goal four minutes after the restart to stretch the Welsh side 14 points in front, but Connacht mustered a revival on 58 minutes with Farley barging over in the left corner. McHugh cut over a superb conversion to put Connacht within touching distance.

The home side roared to the finish thanks to a first McHugh penalty on 61 minutes and 13 minutes from time O'Sullivan clambered over near the posts following a back-row move.