Both former England captains are leaving to join French teams at the end of the season, with the way now clear for 32-year-old fly-half Farrell -- who has been at Saracens since 2008 -- to join Paris-based Racing 92.

Northampton, who finished the regular season top of the table to Saracens' fourth, will now play the winners of Saturday's match between Bath and Sale in a Twickenham final on June 8th.

"It's sad that it's done for a few of us now but we'll look back fondly," Farrell told TNT Sports.

"They got on top of us in a couple of areas and we couldn't get out of our half at times but we showed a lot of heart and fight to stay in the game."

England's record points-scorer added: "I've been here since I was 13 and spent most of my life at this club and I've loved it."

'Found a way to win'

In a gruelling contest, Northampton dominated at the scrum, with Fin Smith capitalising on Saracens' indiscipline to kick five penalties as the Saints reached the final for the first time since winning the title 10 years ago.

"We weren't at our best but to still find a way to win is great but this performance doesn't mean anything if we don't turn up next week," said Lawes.

But the 35-year-old back-five forward added: "We should be expecting to win games like this and we proved we can over the season."

By contrast, defeat also signalled the end of the Saracens careers of two of Farrell's England colleagues in Billy and Mako Vunipola.

"We've got to be grateful for what we've had and what we've done," said Saracens No 8 Billy Vunipola.

"It's life. Everyone moves on. We've had a good run and hopefully the boys can get back next season."

Farrell was only kicking off his left foot in the warm-up, with England international Elliot Daly landing a couple of early penalties.

But Northampton hit back with their first sustained attack of the match, a series of passes and drives taking them into Saracens' 22 before England full-back George Furbank sent in the hard-charging Burger Odendaal.

Smith kicked three more penalties as Northampton moved clear but Saracens responded in style in the 54th minute when Farrell's superb grubber-kick was athletically collected by Alex Lewington for a fine try.

Smith then missed a penalty before Northampton and England scrum-half Alex Mitchell was somehow denied by an extraordinary try-saving tackle from Juan Martin Gonzalez after the flanker raced across field.

But Smith was back on target with a penalty to extend Northampton's lead to 19-13 on the hour and then another success from the kicking tee left the Saints nine points ahead in the closing minutes.

There was still time, however, for Lucio Cinti to run in a converted as Saracens closed to within two points.

But with time almost up and Saracens pressing for another score it was local hero Lawes who sealed victory when the powerhouse forward wrapped up a tackle to create a maul that stopped the visitors' progress.

And when the maul went to ground, the ball was deemed to be unplayable, with the referee whistling for the end of the game to the delight of the Northampton faithful.