Shayne Lavery hit his 20th goal of the season as Linfield edged past Dungannon Swifts to move nine points clear at the top.
On a day when nearest challengers Coleraine slipped up, the Blues made no mistake, beating the League's bottom side to strengthen their grip on top spot.
Jordan Stewart had given them an early breakthrough with his 10th of the campaign, but it was not until Lavery netted the second in stoppage time that the points felt secure.
Boss David Healy said: "It was a really, really tough game and all credit to Dungannon, they made us fight and made us work for it.
"It is what we expected. We knew coming here that it would be tough."
Linfield were never comfortable against a resilient Dungannon side that was much improved from the one that lost heavily to Ballymena United and Glenavon.
But the visitors' quality shone through when it mattered and a superb piece of play led to Stewart's early goal.
The second from Lavery also carried a touch of class, with the striker taking it round a defender before finishing in style.
Dungannon moved the ball well at times, but struggled to make it count.
Healy added: "There were two or three moments where we were a wee bit edgy and a wee bit nervy, but I don't think, as a back four, we gave up too many chances.
"I don't think our goalkeeper had that much to do, even though they had quite a bit of possession.
"Overall I thought we shaded the game, certainly in the amount of chances.
"We probably weren't as good on the ball and kept possession the way we probably should do, and have done in previous games, but if you weigh up the chances, we had more opportunities and probably were unfortunate we had to wait until 90-plus minutes to get the cushion of the second goal."
Healy refused to read too much into Linfield's nine-point cushion at the top.
"One or two of the other teams have a game in hand or a couple of games in hand, all we can do is go and perform and focus on ourselves," he added.
The opening goal came inside four minutes after a high-quality Linfield move. Lavery played in Navid Nasseri and, instead of taking the obvious option and crossing, he slipped in the overlapping Matthew Clarke. He turned the ball across goal, where Stewart had arrived in time to slot home from close range.
Lavery then had a snapshot saved by Roy Carroll, who also did well to keep a Nasseri effort out.
The second half followed a similar pattern, with Dungannon good on the ball, making it difficult. Linfield still carried the greater threat and, just past the hour, a brilliant run from Lavery almost opened the hosts up.
Stewart's shot was blocked, but Nasseri's pass found Kirk Millar, whose low strike was blocked by the outstretched foot of Carroll.
The Swifts' first real chance came in the 70th minute as Ben Gallagher picked up the ball, held off a defender and shot just wide.
Linfield had brought on Andy Waterworth and Christy Manzinga as they looked to close the game out and the pair almost combined for a second goal.
Waterworth's touch released Manzinga, who stepped inside his marker and hit a shot that flashed an inch over the crossbar.
A driving run from Manzinga then drew a free-kick, with Niall Quinn's effort a fraction wide.
Linfield added the second in stoppage time. Manzinga dropped deep to win back possession and played in Lavery, who killed the ball with a great first touch, turned past Matty Smyth and sent a left-foot strike arrowing past Carroll.
Dungannon remain bottom but boss Dean Shiels was a lot happier with his players' performance.
He said: "Linfield are a top team, they are going to create chances and they score in most of their games, so it was how we dealt with that.
"I was really pleased with the players' reaction. The mentality in the past has sort of been to crumble and to roll over, but today we stood up to it and we met the challenge face-on, and I was delighted with that."
DUNGANNON: Carroll 7, McGee 7, Byers 7, M Smyth 7, Glenny 7, Campbell 6 (Teelan, 84 mins, 5), Convie 7 (Forde, 84 mins, 5) O Smyth 7, S McGinty 6 (Patton, 84 mins, 5), Carvill 6, Gallagher 7. Unused subs: Byrne, Coyle, C McGinty, O'Kane.
LINFIELD: Johns 6, Haughey 6, Larkin 6, Callacher 6, Clarke 6, Palmer 7, Quinn 7, Millar 7, Nasseri 6 (Manzinga, 68 mins, 7), Stewart 7 (Waterworth, 67 mins, 7), Lavery 8. Unused subs: Moore, Stafford, Newberry, Pepper, Archer.
Referee: Christopher Morrison 6