This utterly engrossing Old Firm encounter yesterday on a hot Sabbath in Glasgow left only one thing to say – the race for the Clydesdale Bank Premier League title is decidedly back on. From their aimless drift of three weeks back, Celtic have somehow contrived to beat Rangers twice in succession, and if there is any psychological advantage in these situations, it surely now lies with Gordon Strachan’s men.

Indeed, the arithmetic of the league is intriguing. Celtic are now five points clear of Rangers and, due to the fact that Rangers don’t play again until Sunday, that lead could stretch to eight points if Celtic beat Motherwell at Fir Park on Saturday. By that stage, as improbable as it would be, Rangers would have four games in hand, but may also be prone to the jitters.

These teeming Old Firm affairs are a sight to behold, and Celtic had an array of heroes yesterday. Chief among these was Scott McDonald, the little Australia striker who arrived at Celtic Park last summer supposedly as a squad player, but whose two goals yesterday took his tally to 29 for the season. McDonald blew his heart out in this match, running Rangers ragged and leading his side’s attack with sheer menace. He also provoked the hapless Kirk Broadfoot into rugby-tackling him in the box, from which Celtic claimed their match-winning penalty.

Yet McDonald was one of four or five players who were outstanding for Celtic. Barry Robson, another who was due to simply beef up this Celtic squad, was an astute workhorse in central midfield, strong on the ball and imaginative in his play. So, too was Paul Hartley, a selfless worker for his team. And Gary Caldwell, a defender who has attracted sometimes endless flak at Celtic, proved a stalwart who made a series of timely tackles, even though the home side were to look vulnerable at corners in the opening half.

Rangers scored twice through David Weir and Daniel Cousin – both headers from these Steven Davis corners – but in truth they rarely caused Artur Boruc to be leaping around his goal in high anxiety. If Rangers had a justified gripe, it would certainly be that McDonald’s opening goal after four minutes looked to be marginally offside.

It was a day of suffering all round for Rangers. Already without Carlos Cuéllar and Kevin Thomson through suspension, Walter Smith’s side lost David Weir to injury after 50 minutes and then had Steven Whittaker sent off one minute from time for a second yellow card issued to him by Craig Thomson. Smith complained later that Whittaker’s two challenges were “innocuous”, though his red card was quite irrelevant to the result, but he now misses vital games in the championship run-in.

If Boruc was hardly busy, he certainly made himself prominent after the final whistle, whipping off his shirt and throwing it into the crowd before revealing a T-shirt underneath with an image of His Holiness, the Pope, upon it. The Poland international then sauntered around Celtic Park as only he can, displaying an image of the selfsame religious leader whom some Rangers fans had been theologically taking to task just 30 minutes earlier. After an enthralling game, it was all stuff and nonsense.

Celtic had been vulnerable at corners, and Rangers savoured their fragility. Twice within 12 minutes in the first half Weir and then Cousin got their heads to Davis deliveries to force the ball past a startled Boruc. But as the match wore on a collective strength evolved within Celtic, to the point where Rangers could hardly muster a real chance of note in the second half.

The game was scarcely alive when Celtic claimed the lead. A long, raking pass from Andreas Hinkel after four minutes found the head of Jan Vennegoor of Hesselink, whose knockdown suddenly released McDonald behind Weir and Christian Dailly in the Rangers area. One-on-one with Neil Alexander, McDonald, appearing marginally offside, controlled the bouncing ball to sweep his shot past the Rangers goalkeeper.

Celtic, however, having looked composed on the ball, were quickly made to look highly suspect when facing dead balls. Twice Davis would arc in his corners from the Rangers left, and twice Boruc would have to fish around to retrieve it from his net.

First, after 16 minutes, Weir barged between Caldwell and Stephen McManus and craned his neck to reach the ball and send it behind Boruc. Then, 12 minutes later, Cousin made a near-post run to meet Davis’s delivery and nod the ball backwards, watching it scrape under Boruc’s bar and in for Rangers’ second. That made it 2-1 to Rangers after 28 minutes, and now we really did have a game on our hands.

The match had a remorseless and passionate pace about it and Celtic found themselves level three minutes before the break.

Taking Aiden McGeady’s pass into feet just inside the area, McDonald paused and then turned Dailly with fine aplomb to crack his shot at Alexander’s goal. The effort took a faint deflection off Dailly’s outstretched leg, which only helped the ball to loop over the Rangers goalkeeper into the net.

The second half proved quite chaotic. Unfathomably, after 48 minutes, McDonald, when clean through, chose to forego a hat-trick opportunity by squaring a poor pass to Vennegoor of Hesselink, allowing the Rangers defence to clear the danger. The little Australian would have been as well having a pot-shot himself from the slight angle. Then Vennegoor of Hesselink applied an ugly tackle on Amdy Faye, for which he was rightly booked.

At the other end, Novo whistled a shot just a yard wide of Boruc’s right post, though Rangers were about to invite trouble.

Following Hartley’s pass, Broadfoot began clambering all over McDonald from the back on the edge of the area, giving Thomson no option to but award the penalty kick as the pair collapsed in the box.

After a wrestling match for the ball between Robson and Georgios Samaras, the Greece international and former Manchester City striker, the former won the rights and fairly cracked his shot past Alexander to complete the comeback.

Celtic: Artur Boruc 5 Andreas Hinkel 5 Gary Caldwell 7 Stephen McManus 5 Lee Naylor 5 Shunsuke Nakamura 6 Paul Hartley 8 Barry Robson 8 Aiden McGeady 7 Jan Vennegoor of Hesselink 6 Scott McDonald 9 Substitutes: D O’Dea 6 (for McManus, 66min), G Samaras 4 (for Vennegoor of Hesselink, 68), S Brown (for Hartley 82). Substitutes not used: M Brown, P Caddis, M Donati, M Wilson Booked: Robson, Naylor, Hartley, Vennegoor of Hesselink

Rangers: Neil Alexander 5 Kirk Broadfoot 4 Christian Dailly 6 David Weir 5 Sasa Papac 6 Steven Whittaker 5 Brahim Hemdani 5 Barry Ferguson 6 Steven Davis 7 Nacho Novo 6 Daniel Cousin 6 Substitutes: A Faye 5 (for Weir, 50min); J C Darcheville (for Hemdani, 78). Substitutes not used: G Smith, K Boyd, S Lennon, J McMillan, J Fleck. Booked: Broadfoot, Whittaker. Sent off: Whittaker.