Derry required a second half goal from James Kielt to overcome Mayo and get the defence of their NFL Division 1 title off to a winning start at Ballina.
New Derry manager Damien Cassidy had to replace four of his starting players due to yellow cards, but decisively the visitors claimed three crucial late points.
Paul Cartin, Kielt and Paul Young all split the posts in the dying
minutes to move Derry into a winning position, after Mayo had briefly levelled at 0-09 to 1-06.
Mayo established an early foothold, making use of the possession won by their midfield sector to move 0-02 to 0-00 ahead. Andy Moran (after just 47 seconds) and Tom Parsons put their names to the scores.
But by the 20-minute mark, Derry had moved 0-04 to 0-03 ahead with free-taker Barry McGoldrick (0-03) and elusive corner forward Kielt both kicking points.
Nonetheless, the major talking point of the first half amongst the
2,500 attendance was Derry's lack of discipline.
Brian McGuigan, a late call-up for new father Sean Marty Lockhart, was the first to earn a yellow from referee Maurice Deegan. He was replaced by John O'Kane after fouling Trevor Mortimer.
The Oak Leafers had to replace three players in the opening half, with the most controversial moment coming in the 20th minute when Patsy Bradley was rather harshly dismissed for a challenge on Moran.
Just before the break, debutant Brian McAlary joined McGuigan and Bradley on the sidelines but with Mayo struggling to find consistency, Derry still led by 0-06 to 0-05 at half-time.
Alan Dillon was Mayo's top-scorer by that stage, with three points to his name, but both he and his team-mates had been wasteful with their wides tally at six.
With substitute Paddy Bradley beginning to pull the strings, the Oak Leafers edged further ahead during the early stages of the second half.
Kielt blasted home a fine goal, racing onto a flicked through ball
from the influential Bradley, to move the visitors into a 1-06 to 0-07 lead.
Mayo manager John O'Mahony then turned to his bench as he introduced Conor Mortimer and Pat Harte and good play from Mortimer led to a '45' which Ronan McGarrity pointed.
The Connacht side did manage to get back on terms but Derry, with a number of young players showing well on their league debuts, had the legs on their opponents over the closing 20 minutes.
Kielt was the pick of them - the Kilrea clubman top-scored with 1-02 and his goal was effectively the difference between the sides.