The full back trudges off for 10 minutes after TMO and referee decide that it was indeed a dangerously high tackle.

Another spell of Pressure from Sarries, then the ball is flung out to Rotimi Segun on the flank. He tries to go past Kyle Steyn, but he cannot get past and the Glasgow skipper stops him with a brute of a tackle.

But he was also collided into by Kyle Rowe, and they are looking at whether this was a dangerous tackle by the winger and full-back.

A smart kick from Eliot Daly puts Glasgow under pressure by their own corner flag, but excellent defence gives the hosts the chance to clear.

It's much better from Saracens, but no results from it so far.

Saracens get a penalty on halfway which is then moved a further 10 metres after some backchat.

But they waste the chance, Glasgow turning it over before George Horne clears the lines.

Glasgow win a scrum penalty which is kicked to the Sarries 22. Maro Itoje snaffles it and the away side manage to get back to halfway.

Cameras showed the Sarries' squad deep in conversation at the break, I don't think they were "read the Riot Act" but they are playing well in this early phase.

Rotimi Segun slices through the middle and races deep into Glasgow's half. Saracens keep up the pressure until Ben Earl loses the ball in the tackle on the home 22.

The match resumes, it has stopped raining for now at least.

Assuming Saracens don't totally collapse in the second half, we're looking at the following representation of teams in the last 16:

7 from England - Bath, Northampton, Bristol, Harlequins, Leicester, Sale, Saracens

4 from France - Bordeaux, Toulouse, Toulon, Castres

2 from Scotland - Glasgow, Edinburgh

2 from South Africa - Stormers, Bulls

1 from Ireland - Leinster

As it stands, Glasgow are topping the pool. Saracens will go through in fourth, but this display will really worry them with an away tie in the offing. Warriors will be at home - and if it's tipping it down like it is tonight, that won't bother them.

Image source, Getty Images

Very impressive by Glasgow Warriors.

Saracens are keeping the ball really well, but great defence stops that attack.

Huge steal by Rory Darge. Glasgow out of trouble.

Tom English
BBC Scotland chief sports writer at Scotstoun

Gregor Townsend is picking his Six Nations squad on Tuesday. The pecking order on the wing is interesting now. On form, Kyle Steyn and Jamie Dobie are by some distance the first-choice wings. Duhan van der Merwe might be lucky to get in the wider squad the way he's been playing. Darcy Graham is nowhere near his best. Scotland's top-two try-scorers of all-time are struggling to make the 23 for Italy in Rome next month. Steyn and Dobie have been razor-sharp all season. Two very intelligent and influential rugby players outside of 'mere' try-scoring.

Image source, PA Media

Rotimi Segun breaks away and Saracens are deep in Glasgow's 22.

Saracens need to get something before half-time.

Andy Burke
BBC Sport Scotland at Scotstoun

Nobody will fancy coming to Scotstoun to face Glasgow in this form.

Pace, power, precision - it's all on show tonight from the Warriors.

Saracens are yet to get anything going in attack.

Glasgow have been as good as it gets in Europe this season. Properly in the mix. Nice to have a new contender.