Grimsby Town's four-match unbeaten run came to an end as they were beaten by League Two leaders Luton Town at Kenilworth Road.
The Mariners battled well but their hosts found a way through five minutes before the break, when midfielder Luke Berry opened the scoring.
Town started the second half well but their hopes of getting anything from the game were effectively ended just after the hour as James Collins made it 2-0.
The Town starting XI was again unchanged after the deserved draw at Notts County last week, which had followed three successive wins.
James McKeown started in goal, with Zak Mills, Nathan Clarke, Danny Collins and Ben Davies selected in defence.
Siriki Dembele, Mitch Rose, Luke Summerfield and Diallang Jaiyesimi were the midfielders, with Sam Jones and Jamille Matt forming the strike partnership.
The Grimsby substitutes were Ben Killip, Karleigh Osborne, Paul Dixon, James Berrett, JJ Hooper, Martyn Woolford and Scott Vernon.
Luton were looking for a win that would ensure they would spend Christmas at the top of the league, having started the day two points ahead of Notts.
They would look to 13-goal top scorer Danny Hylton and his strike-partner Collins to get on the scoresheet again.
An early shot from Luke Berry was blocked before Olly Lee was stopped by Clarke on the line as the home side made a fast start to the game.
Town's first attack of note saw a ball played forward for Matt but home keeper Marek Stech came off his line to get to it first.
Luton were showing plenty of intent in the early stages, attacking at pace, but the Mariners held firm at the back and had started to settle more by the time the clock ticked past 10 minutes.
A Luton corner led to a shot from Berry but Jones did well to make a block and ensure the ball went away for a Town throw-in.
Hylton saw a shot blocked for a corner by Rose after the striker beat Clarke but the flag-kick was headed away by Mills and Dembele looked to launch a break, only for the ball to be put out for a throw.
A late challenge by Clarke on Luton's Collins led to the Town defender being shown the first yellow card of the game.
Soon afterwards, Summerfield let fly from distance and went close but saw his half-volley drop just wide of the target.
Another home corner came on 22 minutes but Alan Sheehan's delivery was headed clear by Clarke.
At the other end, a long throw from Clarke led to a shot from Mills being blocked for Town's first corner of the game, which was collected by Stech after Summerfield's delivery had been headed on.
Luton's latest corner came when a shot from Glen Rea was blocked by Davies and it led to another when a shot was blocked by Rose after Johnny Mullins had headed the ball back across goal. This time, Clarke headed clear.
The Luton corner count continued to rise and the next one saw McKeown punch clear from a looping header by Dan Potts.
Good play at the other end saw Jones look for Matt with a cross that was put behind for a corner. Collins' header from it went off-target.
Dembele then won a corner on 33 minutes but it came to nothing, before Luton's Collins fired over the bar after a run from James Justin.
A free kick from Sheehan was headed clear by Jones, before another free kick was headed away by Collins after Summerfield was adjudged to have dived.
A high challenge on Dembele led to a yellow card for Andrew Shinnie, before Mills missed the target with a shot.
Soon afterwards, the hosts had their breakthrough as BERRY was given the time and space to pick his spot from 20 yards and curl the ball beyond McKeown to open the scoring with five minutes of the first half left to play.
Luton immediately went in search of a second goal but Lee fired over the bar, before a ball ino the box from Sheehan was cleared by Rose.
Two added minutes were played at the end of the half and with no further chances created by either side before the referee's half-time whistle, the home side's one-goal advantage remained intact at the interval.
No changes were made before the restart and an early shot from Hylton went wide for Luton, before Matt turned and hit an effort that hit the outside of the post after good play by Jaiyesimi.
Jones then had a shot blocked before the ball twice fell to Dembele as Town enjoyed a short spell of pressure but the move ended when Matt was penalised for a foul.
McKeown was booked after he came out of his penalty area and brought Hylton down, with the keeper then claiming the ball after Sheehan's free kick had been heaaded on.
Town were given another opportunity to get the ball into the danger zone with a free kick midway inside the Luton half but Summerfield's delivery from it was poor.
A free kick then came at the other end after a foul by Collins and this time, the hosts made it count by grabbing a second goal when Sheehan's ball was headed into the net by Luton's COLLINS at the near post.
Hooper replaced Jaiyesimi as the Mariners looked to force their way back into the contest but it was Luton who were looking the better of the two sides, with Potts and Berry combining to create their latest opening, which led to a corner that was headed off-target.
A cross from Rose was headed wide by Matt under pressure from keeper Stech, before a first-time shot from Jones was blocked after a run from Dembele.
Harry Cornick replaced Shinnie in Luton's first substitution on 73 minutes, before Vernon came on for Matt in the Grimsby attack.
A volley from Summerfield went well wide three minutes later as the Mariners continued to look for a way back into the game as their hosts aimed to see out the remainder of the contest.
Elliot Lee replaced Collins for Luton and Woolford came on in place of Dembele for Town with seven minutes to go.
Hooper failed to trouble Stech with a shot on 85 minutes, before McKeown was forced to concede a corner as he saved a shot at the other end.
Cornick then went close to getting a third goal for Luton after benefiting from a mistake in the Town defence but Collins did well to get back and do enough to ensure the shot went just wide of the target.
The final substitution of the game came just after it moved into four minutes of added time and saw Hylton replaced by Lawson D'Ath.
Berry had an opportunity to make it 3-0 but McKeown got down well to make the save and ensure the only damage on this occasion would be a corner.
Overall though, the damage had been done as the home side ensured they would be top of the table at Christmas by claiming the three points.
Town are next in action on Boxing Day, when Mansfield Town are the visitors to Blundell Park.
1 Marek Stech
2 James Justin
3 Dan Potts
5 Johnny Mullins
44 Alan Sheehan (C)
16 Glen Rea
8 Olly Lee
11 Andrew Shinnie
18 Luke Berry
9 Danny Hylton
19 James Collins
36 James Shea
39 Akin Famewo
14 Harry Cornick
24 Lawson D'Ath
22 Luke Gambin
17 Pelly-Ruddock Mpanzu
38 Elliot Lee
12 Zak Mills
2 Ben Davies
5 Nathan Clarke (C)
6 Danny Collins
19 Luke Summerfield
20 Diallang Jaiyesimi
8 Mitch Rose
27 Siriki Dembele
29 Jamille Matt
10 Sam Jones
30 Ben Killip
3 Paul Dixon
14 Karleigh Osborne
7 James Berrett
25 Martyn Woolford
9 JJ Hooper
21 Scott Vernon
Attendance: 9,102 (446)
Referee: Christopher Sarginson
Next Up: Mansfield Town