It had been billed as a journey into `Hell' but Chelsea silenced the hostile crowd in Galatasaray's Ali Sami Yen stadium to resurrect their Champions League campaign with a memorable display brimming with assurance.

A strike by Tore Andre Flo put Chelsea on their way to victory after 32 minutes and the Norwegian's second, followed by a solo effort by Gianfranco Zola in a devastating five-minute spell just after the break, wrapped up the match.

By the end, Chelsea were strolling their way to victory amid an almost deathly silence and Dennis Wise emerged from the bench to claim a fourth 12 minutes from time, while even Gabriele Ambrosetti joined in by stroking home the fifth.

The only note of harsh reality - and a considerable one at that - came with the sobering news that Hertha Berlin had defeated AC Milan 1-0 at home and Chelsea now still probably need at least four points from their remaining two games to qualify.

This victory nevertheless marked a selection masterstroke by manager Gianluca Vialli, who not only picked Flo ahead of £10 million signing Chris Sutton but also dropped club captain Wise to the bench before his dramatic late introduction.

Chelsea also coped well with the intimidatory surroundings. Flares were lit, riot police had to shield the players as they walked on to the pitch and a cacophany of abusive chants urged Chelsea to return from whence they came in no uncertain terms.

Having called for cool heads, that is exactly what Vialli got and perhaps it was with that in mind that club captain Wise was dropped to the bench four days after he had been sent off for the ninth time in his Chelsea career at Liverpool.

Chelsea had to defend desperately early on - playmaker Gheorghe Hagi struck the outside of the post with a curling free-kick and smoke from flares started to envelop the pitch as Chelsea struggled to even retain possession.

With Hagi expertly pulling the strings as ever, Galatasaray were making far better use of the full width of the pitch and the visitors were forced to scrap for everything.

Attacking forays by the visitors were few and far between but Chelsea had a valuable ace up their sleeve in the shape of the irrepressible Zola.

After Gustavo Poyet had seen a drive tipped over the bar by inexperienced goalkeeper Bolukbasi Mehmet, the Italian's trickery carved open the home defence on the counter-attack.

The Italian lofted a through-ball into the path of Flo, who was able to bear down on goal as Mehmet, a stand-in for Claudio Taffarel - who was sent off at Stamford Bridge - hesitated fatally on his line.

Flo, who had not scored since the opening day of the season, showed commendable composure as he turned inside defender Gheorghe Popescu and threaded his shot inside the far post.

Chelsea goalkeeper Ed De Goey then had to produce a superb diving save to tip a header from Hakan Sukur onto the crossbar as Galatasaray renewed their assault.

Frank Leboeuf also required treatment after a clash with Popescu but Chelsea resolutely hung on to their lead until the half-time whistle blew and they promptly took the Turks apart after the break.

Within four minutes, they were leading 2-0 as Zola picked out Poyet at the far post and the Uruguay international did well to head the ball back across goal towards Flo. The striker still had much to do but he expertly controlled the ball with his chest and turned in a flash to strike a volley into the far corner.

Galatasaray were rocked on their heels but worse was to follow for them after 54 minutes when Zola broke the offside trap to shimmy his way past Mehmet and roll the ball into an empty net.

By then the crowd were virtually silent and were only temporarily roused when a free-kick flashed across the Chelsea penalty area, while Erdem Arif also came close.

However, they did have considerable cause for anger when Marcel Desailly appeared to trip Hakan Sukur in the box only for referee Vitor Manuel Melo Pereira to book the Turkish striker for diving.

It was their last real threat and they were so exposed at the back that Wise had all the time in the world to sidefoot home Chelsea's fourth goal with 12 minutes.

In the closing stages, even substitute Gabriele Ambrosetti, who has hardly set the world alight since his recent arrival from Italy, joined by striking the fifth.

By the end, the stadium was half-empty - and many of the remaining spectators even clapped Chelsea off the pitch.

Hell? More like heaven for Vialli's side but they must repeat the performance in Milan next week as well as against Berlin in a fortnight's time.

Galatasaray: Mehmet, Popescu, Emre, Arif, Okan, Sukur (Saffet 65), Hagi (Hasan 46), Fatih (Umit 46), Tugay, Hakan, Capone. Subs Not Used: Inan, Ahmet, Marcio, Ergun. Booked: Sukur, Umit.

Chelsea: De Goey, Babayaro, Leboeuf, Desailly, Deschamps (Wise 66), Poyet (Petrescu 66), Le Saux, Ferrer, Flo, Morris, Zola (Ambrosetti 75). Subs Not Used: Cudicini, Hogh, Sutton, Lambourde. Booked: Leboeuf. Goals: Flo 32, 49, Zola 54, Wise 79, Ambrosetti 87.

Referee: V M Melo Pereira (Portugal).