Berwick beat Forfar 5-3 in a controversial thriller at Station Park.
Forfar opened the scoring in the fifth minute after Alan Neill fired the ball into his own net.
Berwick were soon level when Gordon Forrest stooped low to head past debutant goalkeeper Neal Ferrie.
The visitors went ahead in the 34th minute through a Lloyd Haddow penalty after Marc Anthony was brought down in the box.
A minute later Forfar's Euan Donaldson was sent off for a second booking.
Berwick grabbed a third just before the interval when Darren Smith scored from 25 yards and they went 4-1 up in the 50th minute through Paul Ronald.
Forfar pulled one back through an Ian Ferguson penalty, but Ronald netted his second and Berwick's fifth a few minutes later.
Forfar were reduced to nine men when Dave Bowman was sent off, followed by Berwick's Smith. Willie Stewart headed a 90th-minute consolation for Forfar.