In a game of few points, and few clear-cut chances, you sense Glasgow need to keep Ulster out here.

Thomas Gordon tries to be sneaky and pinch the ball from the back of an Ulster ruck, but the referee says the ball wasn't out and awards Ulster a penalty.

The visitors kick to touch.

Scott Cummings knocks on, and Ulster will have have a chance to clear their lines.

John Cooney, around whom so much international speculation is circling, trots on at scrum-half to replace Nathan Doak.

For all you weather fans, it's still throwing it down, and this game is still largely being battled out between the forwards.

Glasgow get the shove on at scrum time, and kick the resulting penalty into Ulster's 22...

Image source, SNS

Rory Sutherland, released by Scotland for this game, replaces Eric O'Sullivan in Ulster's front row.

But Jordi Murphy does superbly to get over the ball and win Ulster a penalty at the breakdown.

The chance goes begging.

Glasgow playing with more purpose at the start of this second period - some strong carries from Scott Cummings take the hosts deep into Ulster territory.

Big chance here...

No changes for either side at the break.

Billy Burns gets us back under way at Scotstoun.

We haven't seen any of Glasgow's usual attacking adventure and flair tonight.

Will they be able to spread the play after the break in these tricky conditions?

Tom English
BBC Scotland's chief sports writer on Radio Scotland

Glasgow are in a battle here, and they're losing it.

They seem to be in a rush. They want to play quickly and go wide, and Ulster aren't letting them do it.

It's been all Ulster since Glasgow opened the scoring. Their discipline has been nowhere near good enough - they've got a lot of talking to do in that dressing room.

Image source, SNS

Johnny Matthews is pinged for a high tackle, and Nathan Doak gestures at the posts with the clock in the red.

The scrum-half's kick scrapes over the crossbar, and Ulster lead as the players head for the sheds.

A dominant scrum sees Glasgow win a penalty.

Can the hosts find some forward momentum as we approach half-time.

Johnny Matthews gets over the ball to win a penalty, which is met with a huge roar from the home crowd.

It's more impressive defence, but the lack of possession and territory in the last ten minutes or so isn't sustainable.

Ulster will fancy their chances if it stays like this.

It's all Ulster now.

Jacob Stockdale barrels his way into the home 22, and the Warriors will have to defend their own line once more.

Rhona Lloyd
Scotland winger on BBC Radio Scotland

Glasgow need to look after their discipline in the middle third of the pitch.

You can only defend your try-line for so long, and their luck run out there.

Sorting that discipline would limit Ulster's time in the 22.

A sloppy penalty goes the way of Ulster as Glasgow fail to release in the tackle.

They have looked disjointed since they took the lead.

Can Ulster make this visit to the 22 count?

Here's a look at the game's only score so far.

Sione Vailanu is at the bottom of that pile of bodies.

Image source, SNS

Glasgow somehow repel phase after phase, and hold the ball up when Ulster eventually force their way over the line - stunning defence.

The hosts will have a goal-line drop-out.

Ulster are on the front foot again, and have a penalty advantage inside Glasgow's 22.

They are hammering on the door.