A few more results like the taming of Borussia Dortmund on Thursday night in the Uefa Cup may prove his point. Or will it? For the second time in a few weeks, Advocaat had shaken a German counterpart to the core only to have his work dismissed by Euroscepticism.
Michael Skibbe, the vanquished Dortmund coach, may well have been speaking from the same script as Otto Hitzfeld, Bayern Munich's eminence grise, had delivered a few weeks earlier in the Olympic Stadium as last season's finalists clung on to their Champions' League status despite being outplayed by Advocaat's side.
"I don't see how you can judge whether Scottish football has improved," said Hitzfeld icily, "because Rangers have no Scots in their team." Not exactly correct, but you knew where Hitzfeld was coming from.
Only minutes after Dortmund's 2-0 defeat in the first leg of the third- round tie, Skibbe stepped into the press room and insisted: "There are only a few Scottish players in the team. The football belongs more to Holland than to Scotland. It's a European team really."
Certainly of the 11 players only Barry Ferguson and Neil McCann were Scottish, but it seems Advocaat is damned if he does use Scots and damned if he does not. Rangers, despite their polyglot squad, are not the worst team in Europe when it comes to giving domestic players a chance. Of those sides who, like Rangers, began the Champions' League in September, Chelsea had a lower percentage of nationals (23.3 per cent compared with 26.4 per cent at Ibrox).
Yet while critics have observed that Dennis Wise is a lone Englishman at the Bridge, few have chosen to say that it reflects poorly on the standard of the Premiership.
In fact, multi-national teams are the norm in the Champions' League. Barcelona have seven Dutch internationals alone, which accounts for why Spaniards form only 35.1 per cent of their squad, the same as Arsenal, and the next poorest figure after Rangers. Manchester United, Real Madrid and Lazio hover around the 45 per cent mark and even self-righteous Dortmund (54.5 per cent) had five non-Germans in the starting line-up on Thursday.
For undiluted football, you have to travel to the clean Nordic air of Rosenborg, who can proudly display a 100 per cent Norwegian label.
Not that Rangers, or their fans, are particularly bothered who pulls on a blue jersey as long as the club progresses on the European stage. Dortmund may have been a pale shadow of the team which came to Glasgow in 1996 in a Champions' League group which also included Juventus, but Rangers have grown since that occasion.
Which was why Thursday night simply went with the form book: Rangers are a better side than Dortmund and proved it and few will be keen to meet them if Advocaat can guide them into the last eight. Indeed, Fabio Capello, the Roma manager, admitted as much on C4 last weekend when he said he didn't mind having drawn Newcastle, "as long as we avoided Rangers".
Of course, the notable scalp of Parma - last season's impressive Uefa Cup winners - in the qualifying stage of the Champions' League hiked Rangers' prestige up a notch or too. The otherwise generous Skibbe, agreed, saying: "Rangers didn't surprise me because they are one of the best teams in Britain. They have some excellent players, which they proved in the games with Bayern. Dick Advocaat is also a good coach, but this is a Dutch style of play he uses here. I liked [Arthur] Numan and [Giovanni] van Bronckhorst, and [Jorg] Albertz was good too, but it was the style of play which defeated us - it was very quick. There are lots of good teams in Europe and to get to the very top, you need a bit of luck too. Dortmund are a club which need to get through the winter and still be involved in Europe, but at the moment it is Rangers who have the biggest say in that."
Advocaat, meanwhile, admitted he is searching for a striker worthy of a pounds 10m offer - which rules out any Scot - to increase Rangers' quality streak. Yet Rod Wallace, whose sublime goal created the two-goal cushion and the man who might be expected to make way if a new man arrived, remains upbeat. "It will be different in Germany but we can go through and then put Europe to bed until spring."Reuse content