Brentford B defeated Barnet 5-0 at The Hive to book their place in the Middlesex Senior Challenge Cup Final. They will face Harrow Borough at Griffin Park in the Final on 16 April 2019.
Brentford took the lead after 12 minutes. Forss took aim from the edge of the box and his strike found the top corner.
A slick move started at the back from Brentford almost had them double the lead just moments later. Theo Archibald was the player who squared it for Forss in the middle, the striker missing the target from around the penalty spot.
Then it was the turn of Finnsson for the second goal. A perfectly weighted clip from Ali Coote found the Iceland international inside the box. He beat the defenders and slotted the ball under the goalkeeper to make it two.
A dominant first half display continued as Nikolaj Kirk flicked a corner kick towards the back post. There was Jarvis Edobor, who tried to make a clean connection with the ball but could only divert it wide on the volley.
The third goal came from a Jan Zamburek cross near the byline on the right side. He chipped it right over goalkeeper Renell Mckenzie-Lyle and onto the head of Forss. The Finnish striker nodded it home to claim his second of the night.
Just before half-time, Edobor and Roy Syla clashed heads on the halfway line. The ball had been up in the air a long time when both tried to powerfully nod it into the other's half. It was a heavy collision and both players needed to be replaced before the break.
After the restart, it didn't take long for Brentford to net a fourth. Coote was challenge on the edge of the box with the ball popping out to Oksanen. The midfielder drilled it through a crowd of players, the goalkeeper only able to tip it into the corner of his net.
Forss might have had a hat-trick just before he was subbed on the hour mark. A ball to him at the far post saw him in space, until a superb last-ditch block from Box saw it diverted wide.
Archibald picked up a yellow card with 71 minutes gone, waiting too late to put a challenge in down the left wing. Brentford had a fifth goal soon after.
Coote was the man creating the goal again, slotting it into the centre for Finnsson. The forward showed great composure to chip it over the keeper and score his second of the encounter.
Patrik Gunnarsson had to be sharp to keep his clean sheet in the final ten minutes. First he was quick to his left to parry away a shot from Antonis Vasiliou. Then he pulled off a sublime double save in the dying moments.
First, he got down low to stop a deflected effort from Dwight Pascal as it fizzed up off the turf. He then got up to throw himself in the way of the follow-up from Benji Agahdiuno.
Barnet: Mckenzie-Lyle; Pascal, Smith, Agyaakwah, Box; Syla (sub Vasiliou 45), Tompkins, Taylor; Bettamer, Barham (sub Connell 46), Kyei (sub Agahdiuno 60)
Subs (not used): Azaze (GK), Adeniran
Brentford B: Gunnarsson; Kirk, Mitchell, Edobor (sub Mogensen 45), Dasilva; Oksanen (sub Hammar 60), Zamburek, Coote; Finnsson, Forss (sub Majka 60), Archibald
Subs (not used): Andersson, Johansson