Chelsea star Maren Mjelde scored last-gasp penalty with NO players around the box due to rare rule

Fans watching the dramatic ending of Chelsea's dramatic Champions League clash with Lyon would be forgiven for being a little confused as the referee implemented one of football's rarely seen laws.

Lyon had a 2-1 aggregate lead with seconds left of extra-time in the quarter-final before Lauren James was brought down in the area to win a penalty that would send the tie to a shootout.

It was so late in the game that the referee Ivana Martincic decided it was appropriate to apply the rule which states that 'additional time is allowed for a penalty kick to be taken'.

When this is applied all other players are ushered away from the penalty area as it will be the final kick of the game with rebounds not allowed.

So as Maren Mjelde stepped up the rest of the players were stood watching from the centre of the Lyon half.

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Mjelde dispatched the penalty in emphatic fashion to send the game to penalties, where luck was on Chelsea's side once again.

After the sides had exchanged misses, US international Lindsey Horan saw her kick saved by Ann-Katrin Berger to put Emma Hayes' side into the last four and keep in tact the dream of an unprecedented treble.

They will face Barcelona in the next round with the first leg at on April 29.

They are bidding to becoming the first English side to win the Women's Champions League.