Goals in each half from Graham Carey and Jake Jervis earned Plymouth a 2-0 victory at Northampton.
Argyle shaded the opening exchanges and Peter Hartley headed over from a corner, but the Cobblers gradually got into the contest and Nicky Adams tested Luke McCormick with a low drive.
Yet it was Argyle who broke the deadlock in the 39th minute when Ryan Watson lost possession and Carey raced clear to beat the advancing Adam Smith.
Ryan Cresswell headed over just before the break as the Cobblers tried to get back on level terms but Plymouth substitute Ryan Brunt flashed a shot just wide after the restart.
Argyle twice went close in quick succession when Carey cut inside and his rasping drive was tipped on to the bar by Smith, who then denied Jervis with a point-blank stop from the ensuing corner.
The visitors always threatened a second goal and Smith again had to be alert to thwart Jervis while McCormick saved Cresswell's header at the other end.
But Northampton struggled to create chances and Jervis deservedly doubled Argyle's lead in the 71st minute when he fired home from a tight angle following Carey's corner.
Josh Lelan got a second caution in stoppage time to round off a poor day for the home side
Source : PA