With a coaching career that spanned almost 40 years with thirteen clubs on both sides of the border now tucked away in football's history books, Archie Knox is the kind of person whose views cannot be ignored.

Which is why his pronouncement that Aberdeen, one of his former clubs, won't have a better opportunity than this season to win the Premiership title, starting by imposing themselves in the important clash with champions Celtic at Parkhead on Sunday.

The 67-year-old, who established himself as Sir Alex Ferguson's lieutenant at Pittodrie and with Manchester United before settling-in as assistant to Walter Smith at Rangers and helping them win half a dozen league trophies, highlighted the loss to Scottish football's top tier of the Ibrox side and of Hearts and Hibs, as the principal reason for the Dons to recognise there's no time like the present to challenge the Hoops.

He insisted, too, that if they they can keep top striker Adam Rooney, who has scored 23 goals in all competitions this season, fit and recognised that Celtic may be weary following their exertions in Milan tonight, they can secure the points.

"Aberdeen are hanging-in there and doing really well," he said, "but this is a big game for them.

"Winning at Parkhead would certainly put a marker down for the remainder of the season and no other team is going to come as close as Aberdeen will to taking the title.

"Sunday becomes the big, big game for them and if they can pull it off I'm sure they can take Celtic to the wire.

"Aberdeen never know when to give up, even when they go behind and that comes from the confidence of having a consistent run and winning games and they also have a couple of goalscorers, Rooney in particular.

"That makes all the difference and if you can get the first goal in a game it gives you the confidence to go on again and build on it. If Rooney stays fit they are going to win the majority of their games.

"Aberdeen haven't had such a prolific goalscorer since Duncan Shearer in the 1990s.

"Even in the 1980s when the Dons were winning titles and cups, who was there who scored so many goals in the Aberdeen side? Frank McDougall was one, but few others."

The 67-year-old, who helped Sir Alex lead Aberdeen to the European Cup-Winners Cup with their famous victory over Real Madrid in 1983, never won a league championship with the Dons, leaving to manage Dundee following that Gothenburg win.

But he looked back on what, he stated, was a very different time in Scottish football.

"Look at Jim McLean, who led Dundee United into for Europe 17 times which is remarkable.

"United and Aberdeen were constantly competing for the championship in a league that had Rangers, Hearts and Hibs, all out of the Premiership at the moment which makes a helluva hole in the league.

"So, if there is any side to come through now is the opportunity to do it because once the three sides I've mentioned re-establish themselves in the top tier and Rangers get rid of all their troubles, no matter what anybody says it'll be back to the Old Firm.

"Celtic have a massive game Europa League in Milan against Inter and that definitely makes all the difference.

"A lot of teams suffer European hangovers because players might not be just at the level of ones who haven't competed in midweek.

"These lads who've been involved will have very little time to recover if they come across little injuries.

" So that has to be taken into account as well as the fact that it's a trip away from home and they get back late.

"All that will have an affect on them, there's no doubt.

"And the way Aberdeen approach the game will also have an affect on it."