Whatever criticisms had been laid at Derry's door in the past regarding their lack of heart were washed away at a soggy Celtic Park.
Laois came to town as many people's favourites to win Division Two but, despite being granted two soft first half goals, they couldn't back up their win over Armagh as Brian McIver's men showed character in abundance.
Every time Derry came close on the scoreboard in an opening 35 minutes they largely dominated, a mistake would put them on the back foot once again.
An early two points lead for the home side had been cancelled out by the time Ross Munnelly hit Laois' opening goal after 11 minutes. The Oak Leafers responded and dragged themselves level but left a huge gap down the middle six minutes from the break, which Damien O'Connor exploited with an unstoppable finish.
The visitors found themselves in front by 2-7 to 0-9 at half-time, but with Chrissy McKaigue turning in a stellar show against Clancy after the break, Derry's dominance grew and they eventually got their reward.
However, Laois were left rueing a controversial decision to disallow an effort from Munnelly that appeared to hit the back stanchion on the goal and come out, only for umpires to signal wide when Clancy put the follow up past the post.
They led by two at that stage and it wasn't long until they were behind, with Emmett McGuckin squeezing it beyond Eoin Culliton for Derry's goal.
Eoin Bradley and James Kielt added points and in spite of the latter's dismissal, the Oak Leafers were able to keep possession and hold on for the win.
Derry: T Mallon; R Ferris (0-2), D McBride (0-1), C Kielt; C McKaigue, M Lynch (0-1), SL McGoldrick; Patsy Bradley, PJ McCloskey (0-1); B McGoldrick, E Lynn (0-1), J Kielt (0-3, 0-1f); C Devlin, E McGuckin (1-3, 0-2f), E Bradley (0-5, 0-3f). Subs: R Wilkinson for B McGoldrick (50), B Heron for Ferris (53), D Heavron for Devlin (64)
Laois: E Culliton; C Healy, K Meaney, P O'Leary; D Strong (0-1), J O'Loughlin, C Boyle (0-1); B Quigley, C Begley; R Munnelly (1-3, 0-1f), G Walsh (0-3f), B Sheehan; D O'Connor, P Clancy (0-1), A Doran. Subs: D Booth for Healy (33), C Kelly (0-1) for Doran (HT), P McMahon (0-1) for Walsh (49), C Coss for Sheehan (59)
Referee: J McQuillan