The good old days are back at the Brandywell if last night's accomplished display is anything to go by.
St Patrick's Athletic, serious title contenders and hopeful of at least a place in the knockout stages of this competition, have been made to look extremely ordinary over the course of the last few days.
On Friday Derry took over from the Dubliners as league leaders and now have left them with just a single point from two Setanta Cup outings.
The scale of Derry City revival since Stephen Kenny's return as manager has been nothing less than astonishing.
The manager himself may have tried to play down the notion that just because he was back at the helm, the glory days of old were bound to follow.
But the plain truth is that this side - and largely the same group of players - just was not capable of playing this well last year under either Pat Fenlon or John Robertson.
Whether that was down to clashes of personalities or merely the upheaval of so much coming and going in a single season is difficult to say. But now that they have started winning matches the confidence the side had a couple of years ago has returned with a vengeance. Quite simply last season they were not capable of scoring the quality of goal from which they took the lead last night in the 38th minute.
It was a succession of one-touch passes, from Aaron Callaghan near halfway to Niall Maginn on the right who directed it straight into the path of Gareth McGlynn to cross.
At first it seemed as though he'd overhit it as it sailed past Conor Sammon but in rushed Ciaran Martyn to sail high and head back in across keeper Brendan Clarke.
Setanta may have the English Premier League this season but they won't screen too many better live goals than that.
The second, right at the start of the second half, may have been a little more direct, but came from Derry's speed of movement, first from Maginn's run down the right and quick centre to Paddy McCourt to drill in from six yards out.
Increasingly the defeat at Windsor Park with which Derry opened both the Setanta Cup campaign and the season as a whole, increasingly seems an aberration, albeit against a good Linfield side.
They remain unbeaten since that night, a run which has taken them to the top of the eircom League and on last night's evidence they can stay there for quite some time to come.
And they'll now fancy their chances in this competition now as well and it's just a pity the fans have to wait until the end of the year for the return against Linfield at the Brandywell.
The one thing which threatens to de-rail them is injuries and both Owen Morrison and Clive Delaney had to be replaced last night to add to an alarmingly lengthy list at this early stage of the season.
Morrison, scorer of the goal which deposed Pat's as league leaders in Dublin on Friday night, lasted only eight minutes before making way for McCourt, who Kenny had hoped to rest.
That was the result of a very clumsy challenge by skipper Jamie Harris and he too had to leave the field.
Pat's, who also made changes from Friday's league game, were disappointing and could not manage a shot on target all night.
Their only real chance came in the 29th minute, with the game still scoreless when Alan Kirby broke free and took the ball around Gerard Doherty but the keeper did well to close down the angle and Kirby's effort hit the side netting.
Derry should have been a goal to the good but for a moment of excess enthusiasm from Martyn in the 18th minute when he rounded keeper Brendan Clarke but from 15 yards out tried to blast the ball through the roof of the net and succeeded only in smashing it against the bar.
DERRY CITY: Doherty, McCallion, Hutton, Martyn, Sammon, Callaghan, McGlynn, Molloy, Morrison (McCourt 8), Maginn (Farren 81), Delaney (Higgins 54).
ST PAT'S ATHLETIC: Clarke, Brennan Partridge, Lynch, Kirby, Fahey, O'Neill (Guy 45), Quigley (Fitzpatrick 71), Harris (Frost 7), Dempsey, Paisley.
Referee: Adrian McCourt (Belfast).