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“2–0 lead is the most dangerous lead” is a cliche so overused it has its own Wikipedia article:
"2–0 lead is the worst lead" (sometimes phrased as "2–0 is the most dangerous lead") is a cliché used in sporting contests, to describe the situation in which one team is leading by a score of 2–0, causing them to become complacent. The phrase is most common in association football, where it is sometimes applied only to the scoreline at half-time. It is sometimes also encountered in other sports where 2–0 is a moderately large lead, such as ice hockey.
The equivalent in rugby league is the “14-nil dickheading,”1 which posits that a team that leads by the exact score 14-0 is at risk of an embarrassing comeback from the opposition. Whether the impending dickheading is considered more likely because it is specifically a 14-0 scoreline, depends on the interlocutor.
Last Friday, the Melbourne Storm gave up an absolute classic of the genre, going into the sheds up 14-0 over the Brisbane Broncos, only to watch as the defending premiers pile on the points and sap the Victorians of their will to live in the second half. That morning, on the other side of the world, York City Knights raced out to a 14-0 lead after 24 minutes before Wigan ran them down, sealing the result, 23-22, with a field goal in the 69th minute before conceding a late try to make it interesting.
We don’t have to overthink this. The funny part of a 14-0 dickheading is watching a team - preferably not your own - squander a handy lead.
Based on data from the last eleven years of the NRL, a team leading by 14 points at any point in the game wins the game 92% of the time. That means 8% of the time, and ignoring the clock, a 14 point lead can be overhauled. For the record, the biggest comeback in the dataset was 26 points, which has actually happened three times but only once since 2016 (Dolphins, 28, defeated Titans, 26, in 2023).
It is important to understand the nuance of this chart. What it is saying is that in all the games where a team was down by exactly two points for at least three minutes of game time (to skip over games where the margin was briefly a certain number between a try being scored and the conversion taken), the trailing team ended up winning the game 35% of the time.
Given this is over 2,000 games of sample size from 2016 to 2026 round 2, including a bit over 1,000 games where a two point deficit has existed for more than three minutes, we directly infer the frequency at which the event has occurred historically is effectively equal to the actual probability of the event occurring in future.
This is not quite precisely the same thing as “the odds of a team winning down by two are 35%.” The actual win probability from that position is roughly 40 to 45%, and depends on the time remaining in the game. In this analysis, a team that takes the lead with a try with five to go, misses the conversion but doesn’t relinquish the lead is treated the same as another team trailing by a conversion in the first half2, even though the win probabilities for each of those scenarios are quite different.
This chart establishes a baseline of what a 14 point lead represents in our expectations. You may not have known it was exactly an 8% chance of a comeback but if I surveyed enough of my audience, the average response would have landed close to 1-in-10. So what happens with a 14-0 scoreline?
This table needs some explanation. The top row is the leading team’s score. The first column is the trailing team’s score. Remember that this score only has to occur for a few minutes in a game to count as an example and that we infer the probability of an event ocurring based its on historical frequency. From this, you can see what the rates of successful comebacks have been from any combination of even numbered scores up to 20.
To find 14-0, we go across the top to 14 and down one row to 0, to find the chance of a successful 14-0 dickheading is 13%. This is noticeably higher than the baseline 8% we got for any 14 point lead. The latter rate is lower, which reflects a greater number of games where the winning team increases their margin to 14 points near the end of the game, a position that is effectively impossible to overcome, and other games where the margin is 14 for a while, on the way to a bigger beatdown.
As we descend down the 14 column, the margin narrows and the probability of the combeback succeeding improves. This makes sense. Unless, that is, a team finds itself in a situation where it is down 14-2. There is a range of scenarios where a team might take a penalty goal and then concede 14 points, or concede 14 points and then take the shot at goal or some combination of. They all respresent a degree of cowardice, lack of self-belief or incompetence. In fact, if the team leading has a double digit score, the lone penalty goal reduces the likelihood of the comeback compared to the situation where the trailing team had scored no points at all.
This is not information on which you could base in-game tactical decisions - the team taking the penalty doesn’t know if it is going to score more points later, and thus move into a different box and improve its probabilities, or if the leading team will make it to double digits - other than acknowledging that two point is, indeed, poo points.3
While the rows and columns form scores, the diagonals show the probabilities of overcoming particular margins. For example, the odds of overcoming a two point deficit range from 49% (4-2) to 32% (20-18). As we move to the bottom right, it is worth remembering that situations in which nearly 40 points have been scored are necessarily much later in the game, certainly in the second half of the match, than a game in which six points have been scored. The clock becomes a more significant factor as to whether the comeback will succeed, as the total score increases.
This chart is the same information as the table but displayed differently. Each curve represents the top row of the table, or the leading team’s score. The x-axis is the same as the first column. Where the x-value intersects the line gives the probability on the y-axis.
Despite the complexity, this helps visualise where probabilities stand out from the trend. I’ve marked 8-4, 16-6 and 14-0 as special scores. A team trailing 14-0 is as likely as a team trailing 14-4 to stage a comeback, acknowledging that 14-4 is likely on the route from 14-0 to victory. If the team leading has 16 points on the board, the best bet for the comeback is to be on six or 12. And being down 8-4 is seemingly better than 8-6, partly because the trailing team is incentivised to score a try instead of playing for a goal and partly because 8-6 is a late game coded scoreline, while 8-4 is a necessary progression to any number of much higher scoring outcomes.
There’s no ideal score to be down. From a win probability perspective, it is always preferable to lead the game or, if trailing, minimise the margin as much as possible. There are more successful pathways to victory than others - going from 14-0 to 14-4 is generally more succesful than going from 14-0 to 14-2 - and these involving scoring tries, rather than kicking goals. All of this is unsurprising in the least because funnily enough:
There is little evidence that 2–0 is the worst lead in practice. In association football, a team leading 2–0 at half-time only goes on to lose the game in about 2% of cases. A 2017 analysis by Sky Sports showed that between August 1992 and July 2017, there had been 2,766 occasions in the English Premier League where a team established two-goal lead. Of these matches, 2,481 resulted in victories for the leading team, 212 ended in draws, and 73 in defeats. In ice hockey, statistics show that if a team builds a two-goal advantage, they go on to win the game in the majority of instances, and that a one-goal lead is far more dangerous. As a result, the cliché is often used in full knowledge that 2–0 is not in fact the worst possible lead.
A 14-0 dickheading is fun and memorable but not necessarily anything special statistically.
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