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Champions Cup last 16: Harlequins v Glasgow Warriors at Twickenham Stoop
Glasgow's Cummings gets early try, Matthews and Horne go over in second half
Harlequins first-half tries for Esterhuizen, Smith and Murley; Riley goes over late on
Centre Sione Tuipulotu starts for Glasgow after recovering from a knee injury
Challenge Cup: Gloucester v Castres (20:00) - BBC Radio Gloucestershire
Harlequins 21-7 Glasgow
The players head down the tunnel as Johnny Matthews gives referee Tual Trainini a piece of his mind.
Peter Wright isn't exactly praising the officials on Radio Scotland - it's fair to say most of the decisions have gone against Glasgow in the first 40.
Image source, PA Media
Cadan Murley
Harlequins take full advantage.
Cadan Murley had a try ruled out earlier in the half, but this one counts after Marcus Smith released him into acres of open space.
Smith splits the posts to the delight of the home crowd.
Harlequins 14-7 Glasgow
As soon as I type that, the TMO intervenes to give another penalty against Glasgow.
This one is for a rather contentious tackle off the ball.
Harlequins 14-7 Glasgow
Glasgow have possession with 30 seconds to go until the break.
They will be absolutely desperate for the half-time whistle and a chance to regroup.
Harlequins 14-7 Glasgow
An 11th (yes 11th) penalty goes against Glasgow, after George Horne stops Harlequins competing in the air by changing his line.
Franco Smith will be concerned by that statistic.
Harlequins 14-7 Glasgow
Chris Ashton
Former England winger on 5 Live Sports Extra
Marcus Smith had no right to score that try, the angle he cut was so sharp.
Marcus Smith
Some lovely feet from Marcus Smith, and Quins lead for the first time tonight.
He gets the ball at first receiver, steps inside George Horne, before another left-footed step takes him over the line.
He converts his own try, and the hosts will think they deserve their lead.
Harlequins 7-7 Glasgow
Sione Tuipulotu is shown yellow after another penalty goes against Glasgow.
All the momentum is with Harlequins.
Harlequins 7-7 Glasgow
Danny Care drops the ball under pressure from Zander Fagerson, but Harlequins are awarded a scrum.
The home set-piece looks rock solid at the minute, and they will back themselves to convert from here.
Harlequins 7-7 Glasgow
All of the decisions are going Harlequins' way now.
Marcus Smith goes to the corner again...
Harlequins 7-7 Glasgow
Rory Darge thinks he's won Glasgow a turnover, but the referee sees it differently and awards the decision to the hosts.
Darge looks up with complete disbelief.
Harlequins 7-7 Glasgow
It's end-to-end stuff at The Stoop.
Glasgow win a penalty at the breakdown, but can't take advantage having kicked to the corner.
Max Williamson claimed the lineout cleanly, but the front jumper is penalised for going in front of the jumper.
Andre Esterhuizen
The pressure tells.
It's all about Marcus Smith, who dinks a perfectly weighted kick into Andre Esterhuizen's path down the right wing.
The South African centre doesn't have to break stride, and gets Quins on the board.
Smith adds the extras, and we're all square in London.
Image source, PA MediaHarlequins 0-7 Glasgow
Quins win another penalty at the breakdown, and Marcus Smith opts to go to the corner.
Can they make this visit count?
Harlequins 0-7 Glasgow
Chris Ashton
Former England winger on 5 Live Sports Extra
How Rory Darge has got back there and won the ball is why back rows are worth the money.
Harlequins 0-7 Glasgow
Almost one of the great Champions Cup tries.
Alex Dombrandt throws a dummy, breaks the Glasgow defensive line, and then offloads superbly to Louis Lynagh.
The Italy winger goes for the corner, but is hauled into touch by the scrambling Glasgow defence.
Harlequins 0-7 Glasgow
Sione Tuipulotu runs straight though Marcus Smith off the back of the scrum, but Glasgow are pinged at the breakdown, and Quins survive.
Image source, PA MediaHarlequins 0-7 Glasgow
Peter Wright
Former Scotland prop on Sportsound
If I was coaching Harlequins, I'd be thinking about subbing Tyrone Green for that quick throw.
It's a coach killer.
Harlequins 0-7 Glasgow
This game is being played at breakneck pace.
Quins look to take the lineout quickly and run from deep, but they get wrapped up and suddenly Glasgow have a scrum in the Quins 22.
This is a fantastic platform to attack from.
Harlequins 0-7 Glasgow
And Danny Care now skews his box-kick to touch.
However, a slack pass is behind Kyle Rowe and the attack breaks down.