Celtic - 3 Rangers - 0: Celtic's timely run to the top of the table has come independent of Rangers' on-field implosion, but that will not make the league leaders' supporters rejoice any less.
At this rate, neutral observers of Scottish football will be relying on Graham Rix enjoying a dream six-month spell as Hearts first-team coach or Hibs mounting an unlikely challenge just to keep the league season interesting. Rix started his tenure at Hearts with a 1-1 draw against Aberdeen at Pittodrie yesterday.
Celtic's victory, which was as comfortable as any in recent Old Firm games, has left Celtic 15 points ahead of their oldest rivals.
It is now a question of when, rather than if, Alex McLeish departs Ibrox. But the damage has already been done this season and it would take an extraordinary collapse from Celtic for the championship to remain in the blue half of Glasgow.
Rangers have made their worst start to a league campaign in 22 years and already face the prospect of not qualifying for Europe for the first time since 1980. David Murray, the club's chairman, doesn't attend matches at Celtic Park, but the pain of this defeat would have been every bit as real, no matter where he was watching events unfold.
"I still want to be the manager of Rangers," said McLeish after this latest setback. "It is a huge gap, but we have to keep fighting. We cannot afford to quit."
Celtic's chairman Brian Quinn yesterday stressed there is a lot of talking to be done before any potential move for Roy Keane becomes a reality.
"There are two separate issues," he said. "One is a footballing issue, whether Roy would fit into Gordon's plans and the formation because the team is playing very well just now and is very settled. That is Gordon's judgment and we have to take that into account.
"The other is the business side, and we would have to wait and see what is proposed. We have heard nothing from Roy Keane, nothing from his representatives and until you see what the proposal is, it is premature to offer a view on that."
Saturday's encounter was significant in the sense it illustrated the very reasons why Celtic should not need Keane to wrestle the trophy from Rangers.
John Hartson finished a sweeping move with typical aplomb for his ninth goal of the season in the early stages before Bobo Balde doubled the home side's advantage with a header from Shunsuke Nakamura's perfect cross.
Ireland's Aiden McGeady, who has flourished since being given a regular starting role by Strachan, sealed victory just past the hour, although his goal owed much to the ineptitude of Fernando Ricksen and the Rangers goalkeeper Ronald Waterreus as anything else.
That third goal was, in a single move, symptomatic of the Ibrox club's season to date and the contrasting fortunes of the Glasgow sides since August.
Guardian Service
CELTIC: Boruc, Telfer, Camara, Balde, McManus, Petrov, Lennon, Nakamura (Agathe 76), McGeady, Maloney (Thompson 57), Hartson. Subs not used: Marshall, Virgo, Lawson, Varga, Wallace. Booked: Nakamura, McManus. Goals: Hartson 12, Balde 56, McGeady 61.
RANGERS: Waterreus, Ricksen, Andrews, Kyrgiakos, Hutton (Lovenkrands 53), Hemdani, Ferguson, Murray, Namouchi, Jeffers, Prso (Thompson 66). Subs not used: Klos, Alex Rae, Pierre-Fanfan, Burke, McCormack. Booked: Andrews, Namouchi.
Referee: D McDonald (Scotland).
