Ian Humphreys
Former Ulster fly-half Ian Humphreys on BBC Radio Ulster

When you step up in class in Europe against the big English teams and the big French teams Joe Marer did exceptionally well to put the pressure on Tom Stewart really early and you saw how Ulster couldn't get as quick set as they normally would like, and they often would do.

Ulster come again and Dombrandt does really well to pinch the call at the ruck.

Quins looks to spread it wide but Smith throws straight into touch.

That was superb, then less so.

Ulster win the throw and the maul is rolling towards the line.

But Tom Stewart loses his footing, the maul collapses and the ball isn't going anywhere.

Scrum to Quins on their own five-metre line.

Image source, Inpho

Nick David is sent to the bin.

I don't think he can have too many complaints about that one, and Billy Burns kicks to the corner.

Ulster have a penalty deep in the Harlequins 22 with Nick David pinged for deliberately knocking the ball on.

We're going to the TMO.

James Hume was yelling for the ball out wide. It's just a question if there was cover or if the centre would have had a clear run at the line.

Image source, Getty Images

It's now Ulster's turn to have a go at penetrating the Quins' defence.

Michael Lowry and Stuart McCloskey have a go through the middle before James Hume is chopped down out wide!

Ian Humphreys
Former Ulster fly-half Ian Humphreys on BBC Radio Ulster

Great awareness from Harlequins and that's just so frustrating for Ulster that they switch off momentarily.

Tommy Seymour
Former Scotland winger on BBC Radio Ulster

Ulster need to get off to a fast start. They can't afford to let the Harlequins get momentum flowing and let them get an early lead if they want to have a chance of winning today.

Quins win the line out but it's messy and Ulster manage to get the ball clear through Michael Lowry.

Marcus Smith tries kicking trough but Kieran Treadwell gets his sizeable frame in the way.

Quins had the knock on advantage but Ulster immediately infringe at the breakdown and Quins have the penalty.

In to the corner it goes...

It's a good position for Quins but Ulster pinch the throw.

It's cleared up to halfway but the hosts come again...

Ulster gather the ball from the kick off and John Cooney sends the first ball into the air.

Danny Care manages to win a penalty as his pass is blocked by Steven Kitshoff, who was getting up from the pile of bodies in the ruck.

Marcus Smith brings play deep into the Ulster 22.

Here we go!

Harlequins are already through, Ulster are looking to join them in the knockout stages.

Here come the teams at the Stoop.

Alex Dombrandt leads out the hosts as the smoke from the pitch-side flames disappear into the London afternoon.

Image source, Inpho

Ulster centre Stuart McCloskey says the province can recover from their heavy loss to Toulouse by beating Harlequins to secure a Champions Cup last-16 spot.

Dan McFarland's team head to Twickenham Stoop on Saturday on the back of a48-24humbling in Belfast.

Ulster have also lost to Bath in Pool 2 of the competition, but defeated Racing 92 at Kingspan Stadium in December.

"Hopefully we can bounce back this week. I think we'll turn it round against Quins," said McCloskey.

"It's knockout for us. I know they are already qualified so hopefully that gives us a slight edge.

"There's a lot of enthusiasm in the group and we performed well and got good results in our three previous games before facing Toulouse so we are not too far away," added the Ireland international, who has been named in Andy Farrell's 34-man squad for the Six Nations.

The calm before the storm...

Image source, Inpho

Image source, Getty Images

Ulster have made two changes to their back row with Matty Rea and David McCann replacing injured pair Dave Ewers and Sean Reffell.

England prop Joe Marler returns from injury in one of three changes for Quins.

Second row Irne Herbst and flanker Chandler Cunningham-South are also recalled for the hosts.

All six of Quins' players in England's Six Nations squad - Marler, Oscar Beard, Danny Care, Marcus Smith, Chandler Cunningham-Smith and Alex Dombrandt - all six of Ulster's players in the Ireland squad - Stuart McCloskey, Jacob Stockdale, Tom Stewart, Tom O'Toole, Iain Henderson and Nick Timoney - start.

Harlequins: Green; David, Beard, Esterhuizen, Anderson; Smith, Care; Marler, Walker, Collier, Herbst, Hammond, Cunningham-South, Evans, Dombrandt (capt).

Replacements: Riley, Baxter, Lewis, Launchbury, White, Porter, Anyanwu, Joseph.

Ulster: Lowry; Baloucoune, Hume, McCloskey, Stockdale; Burns, Cooney; Kitshoff, Stewart, O'Toole, Treadwell, Henderson (capt), Matty Rea, McCann, Timoney.

Replacements: Andrew, Warwick, Moore, Sheridan, Rea, Nathan Doak, Marshall, Addison.

Referee: Mathieu Raynal (Fra)

When Ulster and Harlequins met in 2017 London the Stoop was a winter wonderland.

Ulster ran out 17-5 winners that day. Jacob Stockdale touched down and John Cooney was clinical from the tee.

Both players start today and would dearly love a similar result.

Image source, Inpho

Ulster Rugby's association with Kingspan will end by June 2025 after it was agreed the club's principal sponsor would remain "on-board for a 12-month transitionary period" after the current deal ends this summer.

The sponsorship deal is set to end at the end of the 2023-24 season.

Ulster said Kingspan "agreed" to remain "on-board" for a year to facilitate the club's search for a new sponsor.

The club said Kingspan had "signalled its intention" to end the partnership.

Ulster's association with Kingspan stretches back to 1999.

Ulster's current deal with the Irish firm includes stadium naming rights and sponsorship of the club's senior men's shirts.