Malky Mackay should not have to plead his case or present his managerial credentials to Cardiff City owner Vincent Tan - promotion to the Premier League is testament enough.
If, however, the flamboyant and controversial Tan needed any more confirmation that he should not attempt to fix something that is not broken, then the conclusion of a night of passion and fervour in the Welsh capital should provide the most compelling proof.
As Cardiff closed in on victory in their 106th south Wales derby meeting with Swansea City, one chant among the taunts traded relentlessly between supporters carried the greatest significance.
Mackay, standing rain-soaked on the touchline where he had spent the duration of the 1-0 win, heard his name echoing around the Cardiff City Stadium. The Scot's stock was high among the fans before this game - delivering one of the most memorable days in the club's recent history will only continue its ascent.
It was a vocal statement of faith in a manager who has taken Cardiff City into the top tier, not to mention a major Wembley final in the Carling Cup. It was also a clear message to an owner many fans see as a disruptive force, despite being - and this must be stated for balance - a serious financial backer.
Tan's transformation of Cardiff has been a journey with bumps in the road. The controversial switch which saw the Bluebirds' famous blue kit turn red still rankles and was pounced on with delight by the hordes of Swansea fans under heavy stewardship in one corner of the stadium.
"Are you Wrexham in disguise?" was one of a number of low blows delivered, but the vital shot was landed by Cardiff captain Steven Caulker when he headed Craig Bellamy's corner past Swansea keeper Michel Vorm, who was later sent off in injury time for bringing down substitute Fraizer Campbell.
The blue-to-red move away from tradition has still not been accepted by large portions of Cardiff's followers. The loss of Mackay, should it happen, may be a tipping point.
Mackay made a point of dedicating this victory to everyone at Cardiff City, players, staff, fans and the Welsh capital itself "because these have been a tough three or four weeks to endure".
Toughest of all for Mackay to endure was the departure of his trusted head of recruitment Iain Moody.
He was instrumental, along with Mackay and Tan's money, in bringing in two players who made such decisive contributions to a win that was the catalyst for an eruption of noise and celebration as referee Mike Dean sounded the final whistle.
Caulker, an £8m signing from Tottenham, was the match-winner, while the ruthless, competitive Gary Medel - the £11m Chilean secured from Sevilla - was described as "immense from the first to last minute" by Mackay.
They played in a manner that allowed Mackay to point up the wisdom of his summer scouting and recruitment strategy as these three points moved Cardiff up to 12th in the Premier League.
And yet the uncertainty remains. The speculation continues to surround Mackay. This could be seen as a victory of even greater importance if it further underlines the manager's worth to Tan.
There is no doubt Cardiff's fans are watching developments at Norwich City with anxiety. The pressure on manager Chris Hughton increased after their 7-0 defeat at Manchester City - and should a vacancy arise, Mackay's success at Cardiff may just make him a perfect fit at a club where he is still a popular figure.
And they will hope the upheaval which was still clearly playing on Mackay's mind after Swansea were beaten can be banished before it is too late.
In a purely footballing context, it is hard to see how Tan could do any better than the manager he has at the head of his club now.
Cardiff's players were well-organised and showed fierce commitment to the cause - and to their manager. Mackay's game plan to accept Swansea would have possession, but attempt to restrict it in the most dangerous areas, worked to such an extent that, apart from Michu's early miss and a couple of late saves from goalkeeper David Marshall, it was a relatively untroubled 90 minutes.
Mackay spent the entire game stalking his technical area, in sharp contrast to his counterpart Michael Laudrup, who stayed in his seat throughout. This is by no means the measure of any manager, but it allowed Mackay to be in close proximity to a group of players who are clearly desperate to play for their boss.
And, on this day, recent events must not obscure a landmark win.
Until Caulker's goal, the long-held hostility between the fans bubbled under the surface inside the stadium instead of boiling over.
Around 60 coaches carrying Swansea fans arrived in Cardiff under tight security before beating a disappointed retreat after watching a display that was more style than substance, one which rarely threatened recovery once Caulker had scored.
This was a day for Mackay and his players to savour and - so these elated fans will hope - for Cardiff owner Tan to realise exactly what he has in his emerging manager.