Key was low-key about her key free throws: "I've made them before. I'll make them again. They're just free throws," she said afterward.
The Knights (20-12) will face Class 5A, Area 12 rival Brewer (27-7) in Friday's finals at 12:20 p.m. Arab has won two of three meetings this year, including the Area 12 tournament championship game.
Arab beat Homewood despite making only 1 of 14 from 3-point range, sinking only 9 of 20 foul shots and getting outrebounded 46-39.
"I'm super proud to get the win," Justin Jonas said. "It was not our best effort. ... Every team that goes to the Final Four has a game where they have to fight hard and just show they have the will to win."
Homewood (21-6) led 42-40 with 1:23 to play when Shelby hardy sank a jumper, but the Patriots didn't score again after that, missing five shots, including two in the last 13 seconds.
Arab's Shyan Flack made a basket with 55 seconds left to tie the game 42-42. After a Homewood miss, Arab's Shelby Beam got the rebound and drew a foul, but missed the front end of a one-and-one free throw situation. Homewood missed again, but Beam was there for the rebound again, throwing the outlet pass to Key, who drew the foul.
Video of sequence that led to winning free throws: