Rangers 0-1 Celtic
Celtic won the first Old Firm encounter of the season thanks to an unfortunate deflection off Rangers defender Zura Khizanishvili.
It was a thoroughly deserved victory that not only ended the champions' 100% domestic record this season but allowed Martin O'Neill's side to leapfrog them at the top of the Scottish Premier League.
Celtic produced a controlled display to not only stifle a Rangers midfield bereft of ideas but the usual passion associated with these famous Glasgow derbies.
Both sides had gone into the game full of confidence following good midweek performances in the Champions League.
Alex McLeish stood by the same team that drew 1-1 at Panathinaikos, while O'Neill's side arrived at Ibrox without suspended central defender Bobo Balde.
And with Joos Valgaeren and John Mjallby not yet fully fit, striker Chris Sutton was brought back into defence, while young Liam Miller came into midfield.
Rangers were delighted to welcome back Craig Moore after a long spell out through injury, but the captain almost handed Celtic the lead after 10 minutes.
Moore had the chance to clear the danger but struck the ball against Henrik Larsson, who crossed low into the path of Alan Thompson.
The midfielder ought to have done better than drive the ball off goalkeeper Stefan Klos from 15 yards.
Rangers had started the better, but that inspired Celtic and a Stilian Petrov snap-shot from 20 yards flew a couple of feet over.
The home side struck back and an Emerson drive was heading for goal before being deflected over off Sutton.
Celtic suffered a blow after 23 minutes, when Thompson had to be withdrawn with a calf injury, allowing on-loan Sunderland wing-back Michael Gray his debut.
John Hartson will take the plaudits despite a deflection
However, Celtic came close to taking a deserved lead three minutes from the interval.
Rangers were struggling to clear their lines and Petrov played the ball into the path of John Hartson only for Klos to stretch out a hand superbly to turn away the low drive from 16 yards as it headed for the far corner.
A Peter Lovenkrands effort was deflected just wide as Rangers closed the half without forcing Magnus Hedman into a save.
Rangers were forced to replace Moore with Maurice Ross during the break and found themselves behind after 18 seconds of the second half.
A Hartson cross deflected off the hand of Khizanishvili and crossed the line off the underside of the bar.
Rangers pressed forward without being able to threaten Hedman and were almost caught on the break when Petrov's cross was fumbled by Klos at full stretch and Henning Berg whipped the ball off the toes of Larsson.
Klos then saved at the feet of Petrov after the Bulgarian midfielder was sent clear by Larsson.
Rangers: Klos, Khizanishvili, Berg, Moore (Ross 45), Ball, Capucho (Ostenstad 51), Emerson, Arteta, Lovenkrands, Mols, Arveladze.
Subs Not Used: McGregor, Nerlinger, Hughes.
Celtic: Hedman, Varga, Sutton, McNamara, Agathe, Miller, Lennon, Petrov, Thompson (Gray 24), Hartson, Larsson.
Subs Not Used: Douglas, Sylla, Maloney, Kennedy.
Goal: Khizanishvili 46 og.
Referee: M McCurry.