The quick goal was part of the Long Reach go-as-hard-as-you-can game plan.
"That goal kicked us back into gear. It was a nice play by them and it definitely got us going on the right track, " said Glenelg's Molly Milani, whose team eventually won, 4-1.
"We came back and showed them what we've got," said Glenelg senior forward Mia Astran, who scored twice against Long Reach.
Grace Olson and Gabi Rachuba rounded out the Gladiators' scoring.
The victory advances Glenelg (14-2-1) to next Monday's Class 2A state semifinal game at Paint Branch High School. The Gladiators will play Hereford, an 8-0 winner over Rising Sun, at either 5 or 7 p.m.