Denn reached the Ulster club JFC final following a 2-7 to 1-9 victory over Desermartin at St. Tiernach’s Park in Clones.
Denn led 0-2 to 0-1 at the first water break before a strong second quarter saw Desermartin lead 1-3 to 0-5 at the halfway stage; Eunan McElhennon finding the net on the stroke of half-time.
Ben Conaty replied with a goal for Denn three minutes into the second half but Desermartin fought back to level the game at 1-6 apiece at the second water break.
On 48 minutes, Denn moved three points clear when Brandon Keogh found the net and the Cavan champions held off a late rally from Desermartin to win by a point.
Denn now advance to play Downings in the Ulster JFC final after the Donegal side defeated Sean McDermotts 1-9 to 0-8 in Edenderry.