Despite a mountain of possession, Rangers couldn’t find their way past David Marshall for a second time and trooped off the field dejectedly in the knowledge that only a near collapse from Celtic in the last four games will see the Ibrox side finish the season as champions.
After days of conjecture, McLeish had chosen to take the gamble and pitch Marvin Andrews in from the start – Bob Malcolm dropped to the bench – while Hamed Namouchi replaced Thomas Buffel on the right side of midfield.
Andrews looked relatively comfortable throughout before tiring late in the game and was eventually replaced by Malcolm.
Two points behind Celtic before kick off, Rangers knew victory was imperative if they were to retain any genuine hope of clinching the championship but it was the visitors who started the stronger of the sides.
Bellamy had endured a quiet Old Firm debut when the sides last met in February but he would prove to be a pivotal figure in this contest before hobbling off clutching the back of his leg early in the second half.
By that point, however, the damage to Rangers was already done.
With less than two minutes on the clock Bellamy had forced Ronald Waterreus to spring from his line to block a dangerous through ball with Sotirios Kyrgiakos belting away the rebound.
The Welsh striker turned creator moments later, laying a perfect pass into the path of Chris Sutton who, uncharacteristically, completely missed the ball from a decent scoring position.
Rangers, however, were slow to reach to Sutton’s mistake and Neil Lennon was able to rifle a low shot in on goal that Waterreus did well to parry.
After Bobo Balde then headed over from an Alan Thompson centre, Rangers enjoyed their first real chance of the match.
Namouchi’s sweet through ball sent Nacho Novo scampering in on goal but with two defenders close by the Spaniard snatched at the chance and sent a wild shot high into the stand.
You suspected Rangers may rue that miss and so it proved just four minutes later when Celtic went in front after Gregory Vignal allowed Didier Agathe time to chip over an enticing cross that Petrov met flush on the forehead, the ball arcing into the corner of Waterreus’ net.
For some reason Petrov chose to celebrate his goal in front of the Rangers supporters in the Copland Road stand, receiving a plastic cup in the face and then a yellow card for his troubles.
Rangers’ profligacy had been their undoing for the first goal and history would repeat itself when they fell further behind after 34 minutes.
Kyrgiakos could only head a Ricksen free kick tamely into the hands of Marshall and, within two minutes, Bellamy had put Celtic two in front.
Thompson was the creator, allowed to amble through a series of half-hearted challenges before spraying a pass through to Bellamy.
Kyrgiakos seemed to have ushered the striker into a harmless position but Bellamy cut inside before unleashing a venomous strike that rocketed past Waterreus before the keeper could even move.
It took Rangers until injury time to really test Marshall and the goalkeeper did well to flip a Dado Prso volley over the top before Andrews hammered a header off the crossbar from the resultant corner in the last action of a frenetic first half.
With Thomas Buffel on for Mo Ross, Rangers offered much more in the second half but found in Marshall a keeper in superlative form.
Twice the young Scot denied Novo with brave blocks and when he was finally beaten, after Novo had taken the ball round him, Jackie McNamara was on hand to clear the shot off the line.
With the seconds ticking down – and after Kyrgiakos had seen his header hacked away from the line – Rangers finally got one back when substitute Thompson poked a shot beyond Marshall with 87 minutes on the clock.
A late rally followed – even Waterreus was sent forward to join the wave of attacks – but despite a near constant presence in Celtic’s box for the remaining six minutes, an equalising goal wouldn’t come allowing Martin O’Neill’s men to take all three points and giving McLeish much to think about with just four games remaining.
RANGERS (4-4-2): 25 Waterreus; 21 Ross (Buffel 46), 16 Kyrgiakos, 5 Andrews (Malcolm 82), 18 Ball; 31 Namouchi, 2 Ricksen, 6 Ferguson, 24 Vignal (Thompson 75); 9 Prso, 10 Novo
Subs not used: McGregor, Burke, McCormack, A Rae
Booked: Vignal (31), Novo (40), Kyrgiakos (54)
CELTIC (4-4-2): 22 Marshall; 17 Agathe, 6 Balde, 23 Varga, 4 McNamara; 19 Petrov, 9 Sutton, 18 Lennon, 8 Thompson; 47 Bellamy (Beattie 48 (Wallace 89)), 10 Hartson
Subs not used: Douglas, Henchoz, Lambert, Maloney, McGeady
Booked: Petrov (21), Bellamy (34), Agathe (58), Hartson (85)
Rangers Man of the Match: Marvin Andrews