Cardiff City maintained their three-point lead at the top of the League One table with a home win over Exeter City which plunged the visitors back into the relegation zone.
Having been frustrated by their obdurate opponents during a goalless first half, Cardiff made the breakthrough early in the second as Alex Robertson elegantly controlled Dylan Lawlor's superb long ball before finishing neatly.
Cian Ashford hit the post as the Bluebirds took charge and, although they could not add to their lead, Brian Barry-Murphy's side were worthy winners as they recorded a sixth successive home league victory.
They would have gone five points clear at the summit had second-place Lincoln City and Bradford City, in third, not scored stoppage-time winning goals against Stockport County and Wigan Athletic respectively.
As for Exeter, defeat sees them drop back into the bottom four in 22nd place, two points from safety.
Gary Caldwell's men made Cardiff work hard for a victory which was especially important given the late wins for the teams near them at League One's summit.
The Bluebirds had enjoyed as much as 70% possession during the first half, without truly seizing control of the game.
That was because Exeter were so well organised defensively, dropping deep and protecting their penalty area but also pressing their opponents effectively.
Although goalkeeper Joe Whitworth was called upon to push away a fine 30-yard free-kick from Robertson and Isaak Davies' close-range effort, the Grecians were never on the ropes.
In fact, they posed a threat of their own, particularly from set-pieces, while Jack Aitchison forced Cardiff goalkeeper Matt Turner into a save from a rare open-play attack.
Having defended so solidly during the first half, Exeter might be disappointed by the way they fell behind eight minutes into the second.
Teenage Wales centre-back Lawlor lifted a perfectly weighted long ball over the visitors' defence and into the path of midfielder Robertson, who timed his run forward and controlled exquisitely before firing in for his first goal since 1 January.
Cardiff should have extended their lead when Ashford played a one-two with Robertson and shot against the base of the post, before Yousef Salech's rebound was brilliantly tipped over by Whitworth.
Exeter could not muster another shot on target, and their late attempts to snatch a draw only amounted to Reece Cole's volley over, as Cardiff claimed a deserved win - and their first on Boxing Day since 2012.
Cardiff City: Turner, Ng (Kpakio 80’), Lawlor, Chambers, Bagan, Wintle, Robertson (J. Colwill 79’), Kellyman (Turnbull 79’), Ashford (Fish 90+6’), Davies (Willock 57’), Salech. Subs not used: Tanner, Robinson.
Exeter City: Whitworth, Niskanen, Sweeney, Fitzwater, Woodhouse, McMillan, Doyle-Hayes (McDonald 80’), Brierley (Oakes 80’), Aitchison (Mendes Gomes 80’), Higgins (Cole 65’), Wareham. Subs not used: Bycroft, Swinkles, Francis.
