By the way, you won't have long to wait until the last-eight ties in this season's Champions Cup - they'll take place next week.

Here's the quarter-final draw:

• Bordeaux Begles/Leicester v Toulouse/Bristol
• Bath/Saracens v Northampton/Castres
• Glasgow/Bulls v Toulon/Stormers
• Leinster/Edinburgh v Harlequins/Sale

Paul Grayson
Ex-Northampton and England fly-half on BBC Radio 5 Sports Extra

Some work to do for the brain trust behind that [the lineout] because, with ball in hand, Northampton are more than a match for most teams.

Even with the players they've got on the injury list, they're creating space all of the time.

What a fantastic first half of rugby.

Image source, Getty Images

What a frenetic first half that was! I reckon the coaches will be tearing their hair out at the indiscipline and errors, but it has been great to watch.

They win a penalty and go for touch with a kick, but the lineout is a mess and Castres hack it clear.

Rory Hutchinson then tries a grubber with the outside of the right boot, but it rolls out and that's half-time.

Saints will have the last chance of the half with a scrum on the left inside the Castres half.

Tom Litchfield and Henry Pollock are both dumped into touch after a deft exchange of the ball between the two. There's a bit of afters, but nothing like the eruptions of earlier.

Archie McParland is a real livewire off the base of the scrum, he bursts down the right to exchange passes with Rory Huthcinson before the ball is spilled in the Castres 22.

Castres hoof it clear, then Tyler Ardron is lucky to not get a card for a blatant knock-on to break down a Saints attack.

Paul Grayson
Ex-Northampton and England fly-half on BBC Radio 5 Sports Extra

Around the halfway line, it seems both teams are more than happy to play. Either side could have scored in that little period.

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There are prone bodies all over the place after another frantic spell, but the magic sponge does its trick as we are now back to 15 v 15.

The scrums have been messy and the referee has had to have some lengthy chats with the packs. Which gives everyone the chance to pause for breath...

James Ramm has pulled a hamstring, and Rory Hutchinson's introduction sees a reshuffle in the Northampton backs.

Castres are back to 15 now with Christian Ambadiang and Guillaume Ducat back on the field.

James Ramm bursts through the middle, then the ball is moved right but spilled deep in the Castres 22.

But Ramm was hurt in the tackle and he has limped off, replaced by Rory Hutchinson.

Non-stop incident so far.

Paul Grayson
Ex-Northampton and England fly-half on BBC Radio 5 Sports Extra

They'll take the three and take a minute out of the clock as well.

It's all well and good having a two-man advantage but if you don't have control of the ball, there's not a lot you can do to affect the game.

Castres were going through the pick-and-goes trying to create numbers and then realised they haven't got any numbers!

Easy peasy for the number nine, and Castres stretch their lead despite being reduced to 13 players.

Enzo Herve slides a scudding kick through behind the Saints try line and the home side touch it down, but Castres have a penalty.

Three points when two players down will be a decent return.

Despite being two players to the good, Saints are making many errors and are still pegged in their 22.

Castres will be loving this, but both sides are lacking that bit of discipline.

And lock Guillaume Ducat is shown yellow, reducing Castres to 13 men!

Guillaume Ducat went flying in on Henry Pollock at the ruck, and the home fans are baying for blood.

Castres go close again, spinning the ball to the left flank from in front of the posts but it is too high and goes into touch.

Back by the posts, Henry Pollock is involved in another bit of shilly-shallying, as Bill McLaren used to say.

And all three officials are now looking at the TMO to sort out any punishment.