Two early goals consigned Southport to their first defeat of the Vanarama National League North season at Darlington.
Tyrone O’Neill and an Adam Campbell penalty proved to be the difference between the teams on what turned out to be a disappointing afternoon for the Port.
O’Neill gave the home team the lead after just four minutes and Southport never looked likely to get back into the contest as Darlington took control.
The Port came into this game on the back of successive wins but they struggled to find their stride, O’Neill opening the scoring after finding space in the area before curling the ball home.
The home team were quick out of the blocks, Justin Donawa dragging a shot wide before Campbell added a second on 15 minutes, converting a penalty after Reagan Ogle was judged to have committed a foul.
Darlington continued to press and although clear chances were in short supply, the home team remained in control.
Port manager Liam Watson made three changes at half-time in a bid to alter the course of the game, Jack Doyle, Russell Benjamin and Devarn Green coming off the bench.
The visitors saw more of the play after the break but opportunities were always difficult to come by.
Raul Correia did well to turn and shoot but was denied by goalkeeper Chris Elliott, who also saved from Jack Sampson after the striker had connected with an Ogle cross.
Southport: Hanford, Mohammed (Doyle 46), Ogle, Winnard, Astles, Morgan, Glynn (Green 46) Lacey (Benjamin 46), Correia, Sampson, Bauress.
Subs not used: Albinson, Woods.
Referee: John Matthews
Attendance: 1,331