Paddy Jackson’s spectacular try 20 minutes from time helped Ulster move top of the Guinness PRO12 table as they edged Glasgow Warriors 22-17 in an enthralling contest at Scotstoun.

Ulster maintained their 100 per cent record through four games as Jackson decisively finished off a sparkling team move and their defence kept Glasgow’s relentless late attacks at bay.

The visitors were on top for the majority of the first half with Darren Cave and a penalty try giving them a 15-7 lead at the break – prop Gordon Reid getting the hosts’ lone score.

Finn Russell’s penalty and Tommy Seymour’s seventh try of the campaign did give Warriors a narrow lead after the break but Jackson’s effort ensure just a second Guinness PRO12 defeat at Scotstoun for Gregor Townsend’s troops since November 2013.

Les Kiss made nine personnel and position changes from the 19-8 win over Scarlets last time out but there was no lack of continuity for Ulster as they dominated the early going.

After setting up camp in the Glasgow 22, Jackson missed a fairly straightforward early penalty but made amends on five minutes as he successfully slotted a long-range three-pointer.

Ulster thought they had scored the game’s opening try when Jared Payne crossed the whitewash on eight minutes but the score was ruled out after Iain Henderson dangerously cleared out a ruck in the build-up – the Ireland international earning himself ten minutes in the sin-bin.

But that one-man disadvantage barely slowed the visitors as a magical, jinking break by Charles Piutau on the quarter-hour mark got them into the 22 and the ball was spread wide for Cave to slide over in the corner.

Jackson missed the tough conversion and Glasgow got themselves back in the match as fantastic counter-rucking from the kick-off won them a penalty and they were rewarded for aggressively kicking to the corner when Reid burrowed over from close-range.

Finn Russell – on his 24^th birthday – narrowed the gap to 8-7 with the extras and although Ulster remained on top, it took until just before the break for that lead to be extended.

The TMO had ruled out an earlier Rob Herring score as Rodney Ah You was penalised for a blocking line but this time it was the Warriors penalised with Leonardo Sarto’s no-hands tackle on Piutau handing the Irishmen a penalty try.

Trailing 15-7 at the break, Glasgow needed to register the first points of the second half and Russell’s 47^th-minute penalty did just that before a crucial try from the in-form Seymour ten minutes later.

Alex Dunbar made the initial break and a few phases later, Stuart Hogg’s sumptuous offload sent Seymour over for his seventh try of the campaign before Russell’s touchline conversion gave them a first lead of the day at 17-15.

But a contender for try of the young season from Ulster with a little under 20 minutes remaining proved decisive.

After turning the ball over in their own 22, an incisive break saw Louis Ludik inject some pace before sleek handling got the ball in Jackson’s hands and he held off defenders to slide over and add the simple conversion for a 22-17 lead.

The Warriors produced phase after phase in search of a score that would see them get back in the match but the visiting defence held firm to move them top of the Guinness PRO12 table.

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