Newcastle 4 Celtic 1
Albert Luque proved the unlikely hero as Sam Allardyce tasted victory at St James' Park at the first attempt tonight.
The forgotten Spaniard, who had been promised a chance to prove himself all over again, grabbed his opportunity with a first-half double to leave Scottish champions Celtic reeling.
He and Obafemi Martins combined to hand their side a 3-0 lead at the break as the frailty of the visitors' defence proved more costly than that of their hosts.
The Magpies did not have it all their own way by any means as the Hoops played some neat football, but where Luque and Martins were decisive in front of goal, it took Celtic 72 minutes to find a way past former trainee Shay Given as Scott Brown claimed a consolation strike.
The bulk of a crowd of 30,225, including former Magpies boss Bobby Robson, went home smiling having seen Geremi in particular shine on his Tyneside debut as James Milner sealed the victory at the death.
Although there were several significant absentees on the Newcastle teamsheet with Michael Owen, Joey Barton and Shola Ameobi injured and Mark Viduka just back from international duty, it was the omission of Kieron Dyer's name which was perhaps most notable.
Allardyce admitted yesterday that the 28-year-old midfielder could leave the club because of family problems with West Ham, Tottenham and Manchester City understood to be monitoring his situation.
The talk on Tyneside in recent weeks has been of a new era with a new owner, a new chairman and a new manager in place.
However, no-one more than Luque appears to have taking the sentiment more to heart after a dismal two years since his £9.5m move from Deprtivo La Coruna.
The Spanish international has been derided for much of his time at St James', and with some justification.
But for once, there was a glimmer of exactly why then manager Graeme Souness invested so much money in securing his services.
Unlike so often in the past, he got himself in positions to hurt Celtic, and did so to good effect on 29 minutes to fire home from Milner's cross, repeating the dose three minutes before the break with Nolberto Solano this time supplying the ammunition.
With Martins having already given his side an 11th-minute lead with a right-foot snapshot, the Magpies were in complete control by the break, although it would not be too unfair to suggest the scoreline flattered them a little.
Allardyce is working desperately to strengthen his defence, and the reason was plain to see as the movement of the Hoops front two Maciej Zurawski and Jan Vennegoor of Hesselink at times left them chasing shadows.
However, crucially, the pair were nowhere near as clinical as their Newcastle counterparts when the chances came, and Given was only called into action once when he had to tip Aiden McGeady's deft 33rd-minute shot over the bar.
Luque made way for Andy Carroll at the break as Allardyce made four changes, and but for a miskick in front of goal the newcomer might have announced his arrival with a fourth within five minutes.
If anything, the visitors dominated much of the half with McGeady forcing Given into another, if this time more comfortable, save.
However, defender John Kennedy's careless 55th-minute back-pass let Carroll in with substitute goalkeeper Mark Brown rescuing his team-mate.
Vennegoor of Hesselink fired well wide under pressure from half-time arrival Steven Taylor on 59 minutes, but Milner left Lee Naylor for dead to drill a shot just past the far post two minutes later.
Midfielder Scott Brown set off on a mazy 67th-minute run and crossed to the near post as the visitors looked to save face, but David Rozehnal was on hand to clear.
However, Brown got his name on the scoresheet when he headed McGeady's 72nd-minute cross past Given, and might have doubled his tally within three minutes when he fired across goal after Matty Pattison's slip.
Celtic finished strongly as Allardyce continued to make changes - reserve keeper Steve Harper played the last 11 minutes as a striker - and Given denied Brown a second after he was played in by substitute Kenny Miller.
But Milner wrapped up the win with an excellent last-minute strike with Harper playing a key role in the build-up.