Mayobridge midfielder John Caldwell scored a equalising point deep into injury-time to give his side a draw in the AIB Ulster Club clash at Omagh.
Ronan McNabb scored Dromore's goal in the second minute
Teenager Ronan McNabb hit an early goal and four Colm McCullagh points helped Dromore lead 1-6 to 0-6 at half-time.
But some superb Benny Coulter scores helped Mayobridge draw level with a minute of normal time left.
Sean O'Neill restored Dromore's lead but he was then dismissed for a second yellow card before Mayobridge levelled.
The sides will meet again at Newry next Sunday to decide who meets Crossmaglen in the provincial semi-final.
Goalscorer McNabb, who starred for the Tyrone minors this year, was making his first championship start for Dromore.