And now the pressure is coming on at scrum-time. The heavyweight trio of Vunipola, Geroge and Koch have Leinster in a tailspin.

Up flies the French referee's arm. Penalty. This is on halfway. But Elliot Daly has a siege gun boot and wants the tee...

Image source, Getty

Leinster bash away at the black wall, make little impression and Luke McGrath opts to put up the up and under from the base of a breakdown.

But Saracens have covered off that escape route. Alex Goode claims head, shoulders and torso above everyone else.

Paul Grayson
Former England fly-half on BBC Radio 5 Live Sports Extra

Brad Barritt looks exhausted already. He has got an incredible work rate but he already has some miles on the clock.

Nothing surprising out there from Saracens - but nothing much you can do about their tactics either.

Richard Wigglesworth is launching a barrage of box-kicks, picking out James Lowe for particular attentiion.

Duncan Taylor and Brad Barritt are haring up in defence to put the heat under the Leinster backline.

So far it is working.

Maro Itoje pounces to claim an interception and ease the pressure. The Lions captain-in-waiting (?) grabs the ball just ahead of Will Connors.

Saracens look bang up for this. And Leinster look like they might have been caught on the hop.

This is going to be interesting.

Leinster now with a bit of territory and possession. Jack Conan makes gains inside the black 22m...

Paul Grayson
Former England fly-half on BBC Radio 5 Live Sports Extra

Plenty of boxes ticked so far for Saracens. The question remains how long into the game can they maintain this intensity? They have not come here to surrender.

Well, well, well. We turned up the cremation of a Saracens side, perhaps it will turn out to be another coronation.

This is none-too-clever at all by Leinster.

Scrum-half Luke McGrath gives a pass to Garry Ringrose inside his own 22m when bashing the ball long via the boot was the better option.

Saracens swarm like hornets. Vincent Koch is particularly buzzy around the tackled man.

Peep! Hanging on. And this is a gimme of a penalty for Goode...

Lots of backslaps and shouts from the defending champs.

It is clean and clears the crossbar by plenty.

Well, that looked harsh to me. Johnny Sexton is pinged for having a tug on the ball-carrying arm of Billy Vunipola as the Saracens number eight carries into contact.

Alex Goode is going to call for the tee. 45m out and central....

Paul Grayson
Former England fly-half on BBC Radio 5 Live Sports Extra

Lockdown has made Johnny Sexton grey. He can off-days off the tee but it's a good start for him.

A shonky old strike by Ireland's kingpin, but the ball finds its way over.

Saracens with a superbly executed exit strategy. Richard Wigglesworth with a snow-capped box kick, Alex Lewington with the AFL-style claim over his head.

But Andrew Porter is smart on the floor, clamping down over Jamie George and earning a penalty after giving one away in the opening two minutes.

Sexton is going to take a pot at goal and this should go....

Paul Grayson
Former England fly-half on BBC Radio 5 Live Sports Extra

It's a good start for Saracens and what they deserve. It's good to see the referee stamp his authority on the game early.

Over it goes and Leinster get an early reminder of the efficiency of this Saracens machine.

It could get from Fort William to Falmouth on a single tank.

A couple of big rumbles from Maro Itoje and Saracens are up within 20m.

Penalty advantage to Saracens as Andrew Porter fails to roll away.

And Saracens are going to cash that cheque. Goode chips across field into blue hands to take us back for the gimme of a kick...

Alex Goode gets us up and running and Leinster fluff the kick collect.

A rare blemish on the Pro14 champions book.

Scrum-down and decent attacking platform 30m out for the men in black.

Paul Grayson
Former England fly-half on BBC Radio 5 Live Sports Extra

Leinster are an international side. They have been running at 99% for the last 12 months and their hiccups are not costing them games.

Paul Grayson
Former England fly-half on BBC Radio 5 Live Sports Extra

Despite how many players have left Saracens on loan, they can still put out an XV that can compete with anybody. It's the next eight where they used to be able to field another set of internationals, but now they can't.