A waste as Owen Farrell passes over the head of winger Max Malins.

We return to another Sarries penalty and Farrell opts to go for the points.

Maro Itoje takes it quickly and now Sarries are a metre out.

Both sides are scrapping for every single inch.

This time a counter-ruck from Sarries forces problems amongst Quins' forwards and Saracens are awarded a penalty on the halfway line as Evans comes in from the side.

Marcus Smith's wide conversion attempt goes off-target.

Natasha Hunt
World Cup-winning England scrum-half on BBC Radio 5 Live

It's a fantastic start for Harlequins. They've set a tempo and they're here to play.

What a start, it's brilliant work by Harlequins.

"That's your one," says referee Luke Pearce. He's not a fan of the handbags.

Early pressure from Quins who win a line-out inside the 22.

A maul develops leading to a penalty for the visitors in a strong position. And then there's a bit of afters. This is tense already!

First penalty goes Sarries' way and gives them a chance to clear their lines.

Will Evans guilty of coming in from the side.

Worth noting, Quins have never won at StoneX Stadium in the Premiership.

Referee Luke Pearce gets this crunching semi-final under way.

We take a moment to reflect on Tiffany Youngs, wife of Tom, who lost her battle with cancer this week.

Applause all around the ground.

Natasha Hunt
World Cup-winning England scrum-half on BBC Radio 5 Live

This has got a real big-match feel. You can feel the atmosphere burning.

It's magic out here.

Kick-off is just moments away as the players walk out to a wall of noise.

As always, we want to hear your say on this afternoon's action.

The best way to get in touch is by tweeting us using #bbcrugby

BBC Radio 5 Live

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Image source, Rex Features

Interesting war of words in the build-up this week.

Harlequins back row Will Evans said he could "name a few more intimidating grounds" than Saracens' stadium ahead of their Premiership semi-final.

Sarries host their London rivals at StoneX Stadium on Saturday for a place in the final at Twickenham on 18 June.

The 10,500-seater stadium is sold out for Saturday's game, Sarries say.

Flanker Evans, 25, has made only five appearances for Quins this season because of injury but was one of nine first-team players to sign new contracts in January.

Read more here.

Image source, Rex Features

It is Saracens' first play-off game since they beat Exeter to win the 2019 Premiership final.

The club were relegated at the end of the following season after breaching the Premiership's salary cap rules and won an abridged Championship last season.

This term Mark McCall's side won 17 and lost six of their regular-season matches as they finished second in the Premiership, seven points behind Leicester.

"It's something we've been thinking about or aspiring to be in this position for the last 18 months or so," hooker Jamie George told BBC Radio London.

"To be back in it, it's where we want to be, it's where we feel most comfortable, it's where we feel most confident and generally it brings the best out of us."

Image source, Rex Features

A year ago Quins won a dramatic semi-final 43-36 in extra time at table-topping Bristol.

They carried that momentum into the final a week later to beat much-fancied Exeter at Twickenham as Lynagh scored two late tries in a see-saw battle.

"We know it's going to be a ferocious atmosphere on the field," Harlequins' attack coach Nick Evans told BBC Radio London.

"You look at the way Sarries play, they love that confrontation led by Owen (Farrell), but we're expecting that and we'll stand our ground.

"The guys have talked about what that looks like and what we need to do, and when those types of things happen."

Image source, Rex Features

I've only just recovered from the last Premiership semi-final Harlequins were in.

A year ago Harlequins staged a thrilling fightback to beat Bristol after extra time and reach the Premiership final.

Tries from Max Malins (two), Ben Earl and Luke Morahan put Bristol 28-0 up in as many minutes before Alex Dombrandt replied on the stroke of half-time.

Tyrone Green, James Chisholm and Louis Lynagh scores quickly cut the gap to 28-24 and Joe Marchant's late try sent the game into extra time at 31-31.

Green and Marchant tries either side of Malins' third sealed a remarkable win.

For the sake of my fingers, let's get this sorted in normal time today lads.

Image source, Rex Features

Saracens revert to their strongest possible side as they aim to beat reigning champions Harlequins in the first Premiership semi-final.

England captain Owen Farrell leads a Sarries side that sees Maro Itoje make his 150th appearance for the club.

Saracens: Goode; Maitland, Daly, Tompkins, Malins; Farrell (capt), Davies; M Vunipola, George, Koch, Itoje, Swinson, McFarland, Earl, B Vunipola.

Replacements: Pifeleti, Mawi, Clarey, Isiekwe, Christie, Van Zyl, Lozowski, Taylor.

Quins make two changes from the side that lost a 13-try thriller at Exeter.

Huw Jones returns at full-back, Tyrone Green moves to the wing in place of the injured Louis Lynagh while Cadan Murley replaces Aaron Morris out wide.

Harlequins: Jones; Green, Marchant, Esterhuizen, Murley; Smith, Care; Marler, Walker, Collier, Symons, Tizard, Lewies (capt), Evans, Dombrandt.

Replacements: Gray, Kerrod, Louw, Jurevicius, Lawday, Gjaltema, Allan, Northmore.

Image source, Rex Features

After 24 relentless rounds of Premiership rugby union since September we're down to the last four teams standing in the race for the trophy.

It's Premiership semi-finals time and both ties are back-to-back this afternoon with a place at Twickenham next Saturday on offer for the winners.

Welcome along! Here's what's on the way:

StoneX Stadium: Saracens v Harlequins (13:30 BST)

Mattioli Woods Welford Road: Leicester Tigers v Northampton Saints (16:30 BST)