How could Australia knock England, the defending champions, out of the T20 World Cup? Naturally, this being cricket, it’s complicated.

Should England win their last two group matches, against Oman and Namibia, and Scotland lose to Australia in their last game, then the two British sides will be level on five points. The second qualifier from Group B would then be determined by net run rate.

Where goal difference in football is a simple concept to understand, cricket’s equivalent – net run rate – is more arcane. A side’s net run rate is calculated by taking the average runs-per-over scored by that team throughout the competition, and then deducting the average runs-per-over conceded by the team. So a side who score 160 runs in a T20 match, and then bowl their opponents out for 120 will have a net run rate of +2.0 – the eight runs an over that they scored their runs in, minus the six runs an over that they conceded.

What does this all mean for Group B? Scotland currently have a huge net run rate advantage over England: they have a run rate of +2.164, while England have a run rate of -1.800, giving a difference of almost four runs per over.

It adds up to a daunting challenge for England to overcome this week, especially with Australia proclaiming that they want to send them out.

The crucial figure for England is about the equivalent of about 120 runs, or 12 overs (the exact number depends on the targets that they set or score).

Should they beat Oman and Namibia by a combined margin that exceeds these figures, Australia would not be able to eliminate England through a go-slow victory over Scotland.

England could then only be knocked out if Scotland toppled Australia for the first time ever.

It’s happened before

The bad news for England is Australia have displayed such ruthlessness in a World Cup before. In the ODI World Cup in 1999, Australia tried to eliminate New Zealand. Against West Indies, Steve Waugh’s side took 40.4 overs just to reach their meagre target of 111; Waugh took 73 balls over his 19 not out. Australia took 13 overs to score their final 19 runs.

New Zealand still went through; they had the advantage of playing their last game, after Australia, lifting their net run rate above West Indies. 

With England denied such an advantage, only comprehensive wins on Thursday and Saturday can prevent Australia attempting a repeat.