Cathair Friel's penalty gave the visitors an early lead and Glens keeper Elliott Morris made a vital save to deny Conor McCloskey before the break.
Ballymena United manager David Jeffrey said: “We should have come in at half time more than one goal to the good,” said Jeffrey. “It should have been two or three at least. You can’t be on top in a game for 90 minutes . . . Glentoran were always going to come at us in the second half.
“They started very brightly and we paid the penalty. The simple lesson to the players, you’ve got to capitalise when you are on top.
“If you don’t, you get your pocket pinched. Elliott Morris again made a few great saves. He was named man of the match, so I think that says it all.
“But it was a much improved performance from the lads following the Warrenpoint match, so I’ve got to be happy with that. There was good focus and good pace -- we played much better.
“We brought in young Kofi Balmer into the centre of defence . . . he is only 17 yeas of age. Curtis Allen is a very good player . . . so is Robbie McDaid. Kofi would have learned a lot tonight.
“On occasions he did very well, but on other occasions, he looked like a 17 year old.
“It’s all about giving young people an opportunity. Putting him into a situation like this, front of live television cameras will do him no harm. It’s the only way he is going to learn.
“He can be very proud of his performance overall.
“Incidentally, the wind didn’t help at all tonight -- and that’s both teams included.
“It was blowing all over the place . . . . there was no real advantage for either side.
“It was a good performance from us. I think a draw was probably a fair result overall.”