A power-packed second-half from Leinster Rugby produced three tries and a bonus-point to halve Ulster’s lead at the top of Guinness PRO14’s Conference A.

That return, which featured tries from Seán Cronin, Robbie Henshaw and James Tracy, puts Leinster just five points behind their northern neighbours with two games less played.

Johnny Sexton returned to lead out the champions with Ross Byrne listed at outside centre for the first time in his career.

Jordan Larmour, playing for the first time in three months, almost retrieved Sexton’s first kick out of hand from inside the 22.

Ulster were straight into their stride, winning two lineouts and carrying with dynamism, Billy Burns almost putting Sam Carter into the open.

The organisation and rush of Leinster’s defence forced Michael Lowry and John Cooney into kicks when all other options had been exhausted.

The home side was forced to absorb pressure before Hugo Keenan knocked on Burns’ high ball. Marcell Coetzee and Greg Jones made quick yards only for Ethan McIlroy to spill.

On Leinster’s first attack, Cian Healy was driven back and turned for Jordi Murphy to squeeze out a penalty on the floor.

The ball was kept in play for an extended period as both teams mixed up the run and the kick, Henshaw hammering into McIlroy, Stuart McCloskey getting his hands free to set up a counter.

Referee Andrew Brace spotted obstruction on Ulster chasers as Keenan claimed a garryowen to hand a shot at goal for Cooney to oblige from the left in the 15th minute.

Early replacement Tom O’Toole, on for Marty Moore, drove Larmour into touch in another sign of Ulster’s intent.

Leinster’s first real opportunity came from a penalty churned out from a scrum, Sexton missing from the right.

From the restart, the Blues came calling at speed, Josh van der Flier straightening the line out wide, Byrne’s dummy opening up Ulster’s midfield and smart handling drawing a penalty.

Leinster preferred the lineout to the points, Cronin’s throw finding Rhys Ruddock, Cronin shearing off to go close and Dave Kearney eventually beating Matt Faddes and Burns to the left corner from Jamison Gibson-Park’s flat miss ball for the opening try.

Full-back Keenan made up for being beaten in the air by Lowry by outfoxing Burns with his fine positioning to halt an Ulster thrust.

Then, Caelan Doris followed up a decisive tackle on Coetzee with an agile fetch on the floor for a reward of territory.

Scott Fardy emulated James Ryan with a second steal of Rob Herring’s lineouts and Coetzee was immediately binned for a high tackle on Cronin.

Leinster looked to exploit the extra man, Doris refusing to go down from a carry. Fardy’s quick hands put Kearney in space and Cooney had to be vigilant to deal with a dangerous grubber.

Ulster then had the chance to move back in front, Cooney slotting the points from the left for side entry into a maul.

The slippery movement of Gibson-Park, beating three men, sparked an attack which was defused by Murphy’s opportunistic turnover.

From then, Ulster carried with confidence, Jones earning a penalty when Andrew Porter played the ball off his feet. Cooney struck his third penalty for a four-point advantage at the break.

Leinster were quicker out of the blocks in the second half, Keenan snaring Lowry from Sexton’s rolling kick to force a penalty.

The lineout maul was triggered for another penalty for pulling it down, taking them to within five metres. The rising Doris reeled in Cronin’s dart and the hooker got around to grab the ball as the pack fired for five points.

Suddenly, Leinster were rolling forward in numbers and a lightning surge up the left was prompted by Keenan’s dummy and delivery for Kearney to take a high tackle from McCloskey.

Leinster took the tap-and-go rather than a shot at the sticks, teasing out another penalty. Ruddock’s lineout take led to Keenan’s burst and Larmour’s drive to the line where James Hume kept the wing from grounding the ball. Scrum five.

Gibson-Park moved the ball into the hands of Henshaw, Doris followed up and the ball was whipped left for Henshaw to fend off Cooney and Faddes for the third try.

Then, Cronin sprinted clear from a maul and chipped ahead for Gibson-Park to wrestle Lowry to the grass.

Cooney could not find touch with the clearance and Keenan was sure-handed coming onto the ball to start an attack that was just about snuffed out by Coetzee.

Out-half Sexton duped Lowry to counter from deep and Gibson-Park was on the premises to take the home side well inside Ulster’s half where the Leinster lineout was thwarted by Alan O’Connor.

Ulster were playing from behind and Leinster were inclined to rely on their defence to force the issue, Kearney bundling Burns into touch, chaser Keenan nailing Ben Moxham and Larmour closing in on Hume.

The visitors made their way out of danger by way of nicking Leinster’s lineout and a swift attack concluded with Tracy being penalised at the ruck, Cooney making it a one-score game in the 70th minute.

Coetzee was whistled for loitering on the wrong side of a ruck and Sexton angled a penalty to the 22-metre line.

They were in position and placed a bet on their maul when forcing another decision from referee Brace.

From a five-metre lineout, the extra numbers joined for a physical mismatch, Tracy powering over for the bonus-point, Byrne converting.

The Ulstermen came in search of a losing bonus-point, throwing everything into the end-game.

They were unable to break down Leinster’s defence as the champions accrued all five points at the final whistle.