Until then the outhalf, deputising for David Humphries, had produced an indifferent display, missing three penalty opportunities.

And with Eric Elwood missing from the Connacht side, his replacement Mark McHugh won the battle of the outhalves on the night.

However it will be poor consolation for Connacht, who pushed Ulster all the way, dominating the second half and playing the more inventive rugby.

Admittedly Ulster were missing a handful of big guns, but after leading 12-3 after 22 minutes, they succumbed to a spirited Connacht second-half that had them trailing by a point until Wallace kicked over the necessary close-in penalty on 74 minutes .

Ulster opened up a comfortable lead after 22 minutes, outscoring Connacht by two tries to a single Mark McHugh penalty.

Constable's try came after four minutes when he split open the Connacht defence before skipping around the covering Wayne Munn to touch down in the right corner.

And when Bryn Cunningham replicated a well rehearsed training ground move when latching on to a clever kick-through from Wallace, which the outhalf converted, it looked like Ulster would race ahead.

Yet the hardworking Connacht pack did enough to upset the Ulster front eight, mauling and driving consistently to gain the hard yards.

The result was two further penalties which McHugh converted to keep Connacht in touch, closing the gap to 12 - 9 at half time.

The second half belonged to Connacht and they were given a massive boost after three minutes when Uijs claimed the touch down from a Rown Frost line-out catch and well worked maul from the 22.

It provided the necessary impetus to both sides - Ulster's best scoring chance from Wallace halted by a last-minute Munn tackle.

Both outhalves exchanged penalties to leave Connacht ahead after 67 minutes, but despite dominating play for most of the half, the hosts conceded a 74 minute penalty which Wallace converted for the narrowest of victories.

Connacht: W Munn, T Robinson, P Duignan, T Allnutt, M McPhail, E Elwood, E Reddan, D McFarland, M Uijs, P Bracken, D Browne, R Frost, C Rigney, J O¹Connor, DDillon. Replacements, MSwift for Dillon (9m), R McCormack for McFarland (56m), McFarland for Swift (77m).

Ulster: B Cunningham, J Topping, R Constable, A Larkin, T Howe, P Wallace, N Doak, J Fitzpatrick, N Brady, S Best, P Johns, A Kearney, T McWhiriter, A Ward, W Brosnihan. Replacements, M McCullough for Kearney & S Coulter for Topping (59m), B Young for McCullough (77m).

Yellow cards: Connacht, P Bracken (77); Ulster, J Fitzpatrick (77m).

Refree: Dave McHugh

Scoring sequence

3m McHugh penalty 3 - 0

4 m Constable try 3 - 5

22m Cunningham try, Wallace conversion 3 - 12

23m McHugh penalty 6 - 12

26m McHugh penalty 9 - 12

Half-time 9 - 12

43m Uijs try 14 - 12

55m Wallace penalty 14 - 15

67m McHugh penalty 17 - 15

74m Wallace penalty 17 - 18