McGlynn has the first and final say for Donegal
Donegal 1-11 Down 0-11
Donegal were the more efficient side and could take most encouragement from this useful season-opener at Ballybofey.
An early Frank McGlynn goal proved to be the decisive score in a game that was nip-and-tuck until the end.
There was just over a minute played when McGlynn neatly looped the ball over Stephen Kane, the Down goalkeeper. The Glenfin man started at centre-forward in an experimental Donegal line-up and the 2012 All-Star showed his precision with a sweetly-taken goal.
It was a valuable outing for manager Rory Gallagher, who included six debutants in his starting XV, among them midfielder Ciaran Thompson, who hit three points in a Man of the Match display.
Late in the game, Gallagher also gave a run-out to Cillian Morrison, who has swapped codes having played League of Ireland soccer with Derry City in 2015.
"The reason they're in is to push on everybody in our set-up and do everything they can to get as many minutes of competitive action as they can," Gallagher said. "It's always good to win and show a wee bit of mettle to win."
McGlynn's goal gave Donegal a 1-3 to 0-4 half-time lead. Down could have goaled with their first attack, too, but Cathal Doyle had to settle for a point after Joe Murphy scythed his way through.
Eoghan Bán Gallagher, another of Donegal newcomer, blasted wide after racing in to get on the end of a clever knock-down by Leo McLoone.
Corner-back Jack O'Brien, also making his first start, came up to crack a blistering shot off the Down crossbar during a period of Donegal dominance in the second half.
Two frees from centreback Martin O'Reilly settled the hosts, who had a profitable third quarter with Thompson, Hugh McFadden, Caolan Ward, Paddy McGrath and Odhrán Mac Niallais on the mark.
It was McGrath's first score for Donegal in 63 appearances and he was one of the better performers on a day when plenty of January cobwebs were evident.
Gallagher introduced Michael Murphy off the bench for his 100th game in the county colours and he added a point. Murphy slipped as he pulled the trigger with a late goal chance and Down kept in touch with Peter Turley, Ryan Boyle, Darragh O'Hanlon and Barry O'Hagan landing points.
McGlynn, though, clipped over the game's final point to secure a decent win for Donegal, while condemning Eamonn Burns to defeat in his first game as the Down manager.
"There was a bit of rustiness and a few dropped balls as well as poor decision making," said Down player Caolan Mooney.
"I kicked three wides but we have another week of training to get it right for next week's match against Fermanagh at home.
"There are a lot of boys to come through and there are also quite a few boys at university and we will have the more experienced boys back for the start of the National League".
SCORERS - Donegal: F McGlynn 1-1, C Thompson 0-3, M O'Reilly 0-2f, P McGrath, C Ward, H McFadden, O Mac Niallais, M Murphy 0-1 each. Down: D O'Hanlon (fs), G Johnston 0-2 each, R Boyle, R Mallon, P Turley, C Doyle, A McConville (f), S Dornan, B O'Hagan 0-1 each
DONEGAL - D Rodgers; J O'Brien, E Doherty, P McGrath; E Gallagher, M O'Reilly, C Ward; H McFadden, C Thompson; M Carroll, F McGlynn, S McBrearty; O Mac Niallais, L McLoone, E McHugh. Subs: M Murphy for Carroll (52), C Morrison for McHugh (69)
DOWN - S Kane; M McGee, C McGovern, R Boyle; R Mallon, A Carr, D O'Hanlon; P Turley, C Doyle; J McDermott, C Mooney, J Murphy; G Johnston, A McConville, S Dornan. Subs: D Turley for McDermott (45), B O'Hagan for Murphy (59), M McKay for McConville (59), C Harrison for Dornan (59), P Downey for P Turley (66)
REF - M McNally (Monaghan)