One down, one to gopublished at 16:25 British Summer Time 23 May 2015
Saracens it is, then. But who will be joining them at Twickenham on Saturday, 30 May?
We'll find out in due course. It's time for Bath v Leicester Tigers.
Saracens face Bath in Premiership final on 30 May (14:30 BST)
FT: Bath 47-10 Leicester
Banahan hat-trick as Bath score seven tries
FT: Northampton 24-29 Saracens
Saracens reach fourth Premiership final in six years
Sarries tries from Strettle and George, Farrell kicks five penalties
Steve Marshall and Brendon Mitchell
Saracens it is, then. But who will be joining them at Twickenham on Saturday, 30 May?
We'll find out in due course. It's time for Bath v Leicester Tigers.
Wow, got your breath back? What a super first semi-final. Looking back, it's worth noting that Saracens were only ever behind for about three minutes at the start of the second half. Otherwise they were always level at worst.
But how crucial was Stephen Myler's missed conversion that would have tied the scores at 23-23?
Andrew Priestley:, external What an incredible game of rugby. Usually in SFs, with so much on the line, there isn't much rugby played. But that was special.
Jason Stone:, external Play-offs: Is it right? Saints top most of the season, Sarries scrape into 4th. Sarries go through to possibly win the championship??
Ian Hunter
Ex-England and Northampton full-back on BBC Radio Northampton
"Saracens were the better team on the day. They came here with real intent.
"I don't think they were overly creative - you didn't see any flair. But the big difference for me was that their kicking game was absolutely immense today."
Saracens fly-half Owen Farrell told BT Sport: "It will mean a lot (to win the Premiership final). We have got to work hard this week and make sure we are prepared.
"We have had to work hard to get here. In the last couple of years we have been right up there but things have not gone all our way this year.
"We will put the work in this week and we will look forward to next week's game."
Saracens flanker Jacques Burger told BT Sport: "They are a very big, physical side and we knew we needed to match them. The boys put in one hell of a shift today.
"It is no secret that they have had the better of us the last couple of times and we knew we needed to be at our best. We stood up physically. Every collision we were there."
George Barrett:, external FARRELL!!
Eloquently put, George. England fly-half Owen Farrell has kicked Saracens into the Premiership final.
Saracens are going to Twickenham! They turn the ball over one last time on the Saints 22 and are awarded the penalty, which they take great pleasure in booting away. Referee Greg Garner blows the final whistle and brings to an end Northampton's reign as champions.
Still we play on as Northampton have a penalty and run the ball.
The clock goes red as Owen Farrell kicks off but Northampton will have one last chance. But they're deep inside their own 22 and they can't afford to kick the ball away.
Ian Hunter
Ex-England and Northampton full-back on BBC Radio Northampton
"If Saints are going to win this game, it's going to come down to one moment of individual brilliance."
Northampton are back to within a score as Stephen Myler kicks the penalty. There are 30 seconds left. Is there one last twist?
Saracens are almost there as Tom Wood knocks on inside the visitors' half. But Sarries are penalised at the scrum and Northampton have a penalty. They need two scores so Stephen Myler will go for the posts.
Ian Hunter
Ex-England and Northampton full-back on BBC Radio Northampton
"Saints have never had the momentum during this game. I don't think Saracens have done anything amazing to win this, but their defence has been absolutely fantastic."
It's over and surely that's it? Owen Farrell is the coolest man inside Franklin's Gardens as he strikes the ball precisely between the sticks. Those three points extends his lead at the top of the list of points-scorers in Premiership semi-finals.
Could that be that? Billy Vunipola turns the ball over on the Saints 10-metre line and Northampton are penalised. Owen Farrell will have a kick to win this from around 45 metres.
Saracens run through the phases inside the Northampton half. They're running the clock down and Northampton, chasing the game, are at the wrong end of the park.
Ciaran Zanna:, external Being a Saracens fan and with my luck a late twist is on the cards I think. I hope not though!!!
Northampton are running out of time here. That scrum has to be reset and Saracens are then awarded a free-kick, giving Owen Farrell the chance to kick the ball deep into the Northampton half.
Joe Townsend
BBC Radio Northampton
"You can feel the tension in Franklin's Gardens that then erupts into cries of elation at every refereeing decision. Saracens are camped on their own line but so far Saints can't find a way through.
"The champions are clinging on to their title by a thread, with boss Jim Mallinder now using all his replacements. I can taste extra-time."