Arsenal emerged from a bad-tempered battle to knock holders Chelsea out of the FA Cup thanks to a late two-goal entrance by substitute Sylvain Wiltord to reach the quarter-finals.

After six bookings in a period of absolute mayhem towards the end of the first half - both London clubs may hear from the Football Association considering there were at least two instances of mass-brawl scuffling and clearly-implied personal threats - Thierry Henry fired the Gunners ahead from the penalty spot in the 52nd minute.

Jimmy Floyd Hasselbaink brought Chelsea back into the tie with a ferocious finish 10 minutes later - his 18th goal of the campaign, one more than Henry.

But Wiltord, who also scored twice in the previous round's 6-0 demolition of QPR, jumped off the bench 20 minutes from time and made Arsenal's French connection work with cool finishes from a long ball forward by Igors Stepanovs four minutes later and midfielder Lauren's right-wing run six minutes before the end.

Arsenal deserved their success against a Chelsea side who just cannot win away from home.

They should have been ahead before the interval, notably when Freddie Ljungberg shovelled a great chance wide after a piece of sublime skill by the irrepressible Henry and, more obviously, when Dennis Bergkamp was blatantly tripped by Celestine Babayaro as the pair got up from a tangle in the penalty area after goalkeeper Carlo Cudicini grabbed a through ball.

The ball was still in play and Babayaro should have been shown a red card but referee Graham Barber missed it all as he trotted back towards the halfway line.

The incident, however, sparked what had already been a physical contest into sheer bloody-mindedness.

Lee Dixon, captaining Arsenal in the absence of the suspended Tony Adams in his 584th appearance, had already been booked for a routine foul.

But then Dennis Wise and Patrick Vieira grappled with each other after a poor challenge by the Chelsea captain on the touchline.

Henry and Hasselbaink waded in and both were lucky to be only booked, as was Wise. Once all that died down Slavisa Jokanovic was yellow-carded for failing to retreat 10 yards from an Arsenal free-kick. Barber ignored Vieira's shove on the Yugoslav but then booked Stepanovs for a foul soon afterwards.

After all the feuding and fighting in the last 12 minutes of the first half we might have feared the worst when Vieira and Wise went lunging into each other again in the opening minute of the second, the Arsenal man being given a free-kick.

But it was an injudicious challenge by the lightweight Jesper Gronkjaer, finally brought on after the interval to give Chelsea some width, which opened the game up again in a way Chelsea coach Claudio Ranieri certainly did not want.

The winger tracked Lauren into the Chelsea box as Henry pumped over a long cross from the left in the 51st minute and, in total panic, pushed him over from behind.

Henry potted the penalty after a delay for Chelsea's fruitless protests to die down and there seemed no reason after that, with Stepanovs and Oleg Luzhny steady as rocks as Arsenal's makeshift centre-half pairing, they should not go on and win comfortably.

Hasselbaink, though, revived the Blues with a moment of sheer magic 10 minutes later.

Poyet picked him out on the edge of the box and as he turned the big striker shrugged off the challenges of Stepanovs and Luzhny to blaze an unstoppable drive past David Seaman.

This, surely, was Chelsea's cue to take over and they would have done had Gronkjaer's fellow substitute Eidur Gudjohnsen had an ounce of luck with his finishing from a flicked-on corner by Wise soon afterwards.

The Icelander instantly hooked his right foot round the ball but five yards out but saw his effort crash back into play off a post.

It looked like the turning point of the contest as Arsenal grittily wrested control again, but they needed somebody apart from Henry to finish off their superiority.

Enter Wiltord. The £13million record signing, so often left on the bench this season, emerged into the north London sunlight to leave Chelsea doubled up with the quality and panache of his finishing.

Four minutes after replacing the tiring Pires he nipped behind Chelsea's central defence like a latter-day Ian Wright to latch on to Stepanovs' long ball forward and delicately lifted his shot over the helpless Cudicini.

Ten minutes later he set the seal on a notable Arsenal triumph with a short-range jab after the persistent Lauren won the ball back from Babayaro on the right and took it to the byline before pulling back a low cross which was an invitation for Wiltord to score.

That third goal was a bonus for Arsenal, who had already brought on the combative Nelson Vivas in place of Bergkamp to nail down the midfield.

But the Argentinian played a full part in the build up to Wiltord's second match-clinching goal which saw them through despite the never-say-die spirit of Hasselbaink, who saw a thundering free-kick shot deflected away right at the death.

Teams:

Arsenal: Seaman, Dixon, Luzhny, Stepanovs, Cole, Ljungberg, Vieira, Pires (Wiltord 69), Lauren, Henry, Bergkamp (Vivas 81).

Subs Not Used: Manninger, Malz, Kanu.

Booked: Dixon, Henry, Stepanovs.

Goals: Henry 52 pen, Wiltord 74, 85.

Chelsea: Cudicini, Ferrer (Stanic 83), Desailly, Terry, Babayaro, Jokanovic, Dalla Bona (Gudjohnsen 46), Wise, Poyet, Hasselbaink, Zola (Gronkjaer 46).

Subs Not Used: de Goey, Leboeuf.

Booked: Wise, Hasselbaink, Jokanovic.

Goals: Hasselbaink 62.

Att: 38,096

Ref: G Barber (Tring).