Farrell stars as Saracens edge Sale in English Premiership final thriller
The England fly-half kicked 13 points and also shone with ball in hand during a match briefly interrupted by Just Stop Oil protesters.
But the game was still in the balance until Saracens scored two tries inside the final quarter, through Elliot Daly and Ivan van Zyl.
They then survived playing the last six minutes a man down after replacement prop Robin Hislop was yellow carded.
Sale's first final since being crowned champions in 2006 took place against a backdrop of crisis for the English club game, with both Wasps and Worcester expelled from the Premiership after going into administration -- and London Irish in danger of following suit.
This match had been billed as a contest between Farrell and Sale counterpart George Ford, who have 106 and 81 England caps respectively.
It was the second successive season where the childhood friends had faced off in the final, with Ford turning out for Leicester in their 15-12 win last term.
But Australia boss Eddie Jones, who coached the pair when in charge of England, had warned earlier this week that the forward packs would decide a contest featuring the "abrasive" Farrell and the "tactical" Ford.
And it was Saracens forwards who did just enough to give Farrell a chance to show off his all-round game.
Saracens led 6-3 after 14 minutes following two Farrell penalties and one from Ford.
Sarries lost hooker Jamie George to what appeared to be concussion in the 10th minute after he charged into England team-mate Tom Curry.
Play was briefly halted midway through the first half with a game level at 6-6 when two protestors wearing 'Just Stop Oil' T-shirts ran on to the field and sprinkled orange powder on the pitch before being removed by security staff.
Soom after the restart, Saracens went ahead through a penalty try, with Curry sin-binned for his off-the-ball tackle on wing Max Malins.
But Sale drew level when hooker Akker van der Merwe barrelled over from close range for a converted try.
But Saracens led 20-13 at half-time when Farrell's excellent pass to Malins allowed the wing, running an excellent line, to sprint clear for a try.
Sale, however, hit back early in the second half when Van der Merwe burst through and kicked to the corner.
Saracens replacement Daly failed to gather and his hesitation allowed Tom Roebuck to kick ahead and dive acrobatically on the ball for a try. Ford could not convert from wide out but Saracens' lead had been cut to 20-18.
Another Farrell penalty edged Saracens into a five-point lead before northwest side Sale went ahead for the first time in an end-to-end contest.
Replacement prop Bevan Rodd, not long on the field, forced his way over after a fine break by England centre Manu Tuilagi.
Ford converted and Sale were 25-23 up after 54 minutes.
Daly was then just off target with a long-range penalty but his moment came in the 67th minute as he finished a Saracens breakaway with a try after outpacing Rob du Preez at the corner.
Farrell, however, missed the conversion from wide out and Saracens now led 28-25 heading into the final 10 minutes.
And following a lengthy review by the television match official, after referee Luke Pearce had initially ruled 'held-up', Saracens were awarded another try when scrum-half van Zyl went over despite a despairing last-ditch challenge by Joe Carpenter.
