Olivier Dacourt and Ian Harte rejoice at the San Siro (RossKinnaird/Allsport)

Although they were unable to hold on to Dominic Matteo's first- half advantage and become the first English side in 43 years to beat Milan in the San Siro, David O'Leary's braves earned a reward that must not be tarnished.

Despite another example of why Danish referee Kim Milton Nielsen should never be allowed to referee English teams again, O'Leary's side buckled only from Serginho's superb finish midway through the second period to eliminate Barcelona from the Champions League and go through with the Serie A side.

Nielsen, who sent off David Beckham in France 98 and also controversially red-carded Arsenal's Thierry Henry last season, got it badly wrong once more as he cruelly awarded a penalty for handball against Gary Kelly when the Ireland defender had no chance of getting out of the way of Serginho's attempted cross.

But Andriy Shevchenko hit the spot-kick against the outside of the post and a minute before half-time Matteo met Lee Bowyer's corner with a header that flew into the back of the net to create a moment of history.

Inspired by the determination and courage of captain Lucas Radebe, Leeds seemed set to hold out despite a constant Milan barrage.

Serginho ensured they could not as he found a way past Paul Robinson but the draw was sufficient to mean the entreaties - moral rather than financial - of Barcelona counted for absolutely nothing.

Irrespective of Milan's motivation, this was one of the Elland Road club's greatest successes. It should be remembered for their performance, not the nonsense that had gone before.

The equation for Leeds could not have been clearer at the opening whistle - a draw represented the gateway to the next phase.

The question was how Milan, already through, would approach the game, although a glimpse at their line-up, including Paolo Maldini, Demetrio Albertini, and the international strikeforce of Leonardo, Oliver Bierhoff and Shevchenko suggested this was no exercise.

That made the absence of thigh muscle victim Jon Woodgate all the more crucial. Fortunately O'Leary was able to call on the experience of skipper Radebe after two concussive injuries left him on the periphery for two months.

Radebe's importance was emphasised instantly, the South African stepping in brilliantly to dispossess Serginho after the raiding Brazilian wing-back had skipped past Bowyer and Eirik Bakke to surge towards the Leeds box.

The real problems came when Serginho was on the ball, his pace causing huge problems for Kelly, and when the Ireland defender hauled the Brazilian down, Robinson was relieved to see Albertini's free-kick flash across goal.

Alan Smith's willingness to run down any cause ensured Milan were at least discomforted, although Leeds struggled to get players forward in support of the front two.

Mr Nielsen's penalty award, however, seemed to have handed Milan a vital advantage.

But while Robinson, completely outfoxed, dived the wrong way, Shevchenko's studied effort clipped the outside of the keeper's right-hand post.

The relief in the Leeds ranks was total, although Mr Nielsen's eccentricities raised hackles again when he penalised Danny Mills for an alleged foul on Bierhoff that led to Robinson saving from Albertini.

Leeds sensed they could not trust the official. They could trust Radebe though, and the captain.

Just before that, Bakke had been so close to getting a decisive touch to Ian Harte's free-kick, but after Robinson saved well from Serginho, it all changed on the stroke of the interval.

Mark Viduka's persistence down the right forced a corner, and when Bowyer delivered to the near post, Matteo escaped the attentions of both Roque Junior and Shevchenko to flick home, with keeper Dida only able to help the ball on its way.

Now, Mr Nielsen notwithstanding, it just required 45 more minutes of the courage and strength of will to qualify.

Three times at the outset of the half, Robinson's goal was under threat. Shevchenko and then Serginho fired wastefully over, before the keeper saved from Leonardo.

But the keeper could do nothing as Serginho's 68th- minute advance took him beyond Kelly to pick his spot. Yet a draw was enough. Leeds deserved to celebrate.

Teams:
AC Milan (3-4-1-2): Dida; Roque Junior, Chamot, Maldini; Helveg, Albertini, Gattuso, Serginho; Leonardo (Boban, 53min); Bierhoff, Shevchenko.

Leeds (4-4-2): Robinson; Kelly, Mills, Radebe, Harte; Bowyer, Bakke, Dacourt, Matteo; Smith, Viduka. Booked: Dacourt.