David Rainey hit two goals in 10 minutes for the Crues

Ballymena's Simon Kelly hit the woodwork early on while the home team's Gary Haveron also went close.

Teenage defender Johnny Flynn put Ballymena ahead on 63 minutes but Rainey's two goals on 71 and 81 earned the Crues a decider against Glentoran.

Ballymena boss Tommy Wright was booed by some home supporters after the game.

The home side held the edge in the first half and Kelly was unfortunate to see his 35-yard free-kick come back off the woodwork in the eighth minute with Greg Shannon totally beaten.

Crusaders suffered a blow in the 17th minute when former Linfield defender Andy Hunter had to be taken to hospital after suffering suspected ankle ligament damage.

As the Crues attempted to regroup, Haveron went close to adding to Ballymena's lead but his towering header was kicked off the line.

Crusaders' only first-half effort of note came in injury-time when Sean O'Neill moved smartly to stop a Rainey effort.

Flynn, making his first start for Ballymena after a debut outing as a sub against Glentoran on Saturday, hammered Ballymena ahead on 63 minutes from close range after Kevin Kelbie's effort had come back off the woodwork.

But Ballymena's lead lasted only eight minutes with Rainey running onto a through ball and blasting to the net with the home defence caught square.

Rainey repeated the dose 10 minutes later with an accomplished finish from 18 yards after he had run onto another long ball.

The striker has scored five of Crusaders' seven goals in this season's Shield.

Crusaders will face Glentoran in the final on 30 October.