Leo Cullen came away from the first real test of his tenure with nothing more than a losing bonus point as Leinster lost out to Edinburgh 16-9 on the opening night of the PRO12 League at Meggetland.
The Irish eased in front from an Isa Nacewa penalty in the 17th minute for a high tackle on out-half Cathal Marsh, as both clubs struggled for any sort of rhythm.
The equaliser came from the boot of scrum-half Nathan Fowles when Dan Leavy infringed in the 25th minute.
It stayed that way to the break as neither club could establish any real dominance in a match that had the feel of players searching for form and fitness.
Leavy made up for his indiscretion by shaking the ball free from flanker Roddy Grant to prevent a certain try. However, Edinburgh lock Cornell du Preez's offload allowed wing Damien Hoyland to find a metre of space to squeeze in at the left corner for 8-3 in the 55th minute.
Leinster responded quickly, their sound driving play creating the pressure to force a penalty, which Nacewa struck, to leave two in it in the 58th minute.
The damage was repaired when full-back Jack Cuthbert found the posts before Nacewa held his nerve to make it 11-9 in the 73rd minute.
Dominic Ryan was binned late on as Edinburgh finished on the attack - and in control.
They had the composure to hold onto the ball close-in before releasing it wide for Hoyland to wrap it up with his second try.