The date effect’ is a common recruiting phrase used to describe the gulf between athletes born before and after July.

Generally speaking, players born earlier in the year are considered to be ahead in their physical development compared to those born in the second half of the year.

A result of this is that often late-birth players (particularly those aged around 15-16) often miss out on selection for elite junior squads as they’re competing against more developed kids who are sometimes up to 6-10 months their senior.

This theory has been reflected largely in recent AFL elite junior squads and Drafts, where a significantly greater number of ‘older’ selections were chosen ahead of the ‘younger’ counterparts born in the same year.

It also translates in younger talent groups across all sports, with children born in the first half of the year usually having greater representation than children born in the second half of the year.

But the Brisbane Lions seem to have bucked the trend.

In fact, if you take a look at the Lions’ drafting over the past three years, you will find that 13 of the Club’s 20 selections (or 65%) have been born in the second half of the year. This essentially means that the majority of their recently recruited players are less advanced in terms of their physical development.

Lions National Talent Manager Rob Kerr said the Club doesn’t necessarily prescribe to ‘the date effect’, and instead focusses on identifying the best possible athletes - regardless of their birthdate.

“It hasn’t been a conscious decision by our recruiters, it just happens to have worked out that way,” Kerr said.

“We simply select the best player to fit our team needs - age doesn’t come into our decision-making, but we know their rate of maturation will impact their performance in their early years.”

“In terms of their developmental age, they’re probably behind their peers who were taken in that same year. Also, the variation in maturation rates means that the gap can sometimes be further exaggerated.”

“But we look at our young draftees being long-term contributors to the Club’s future, and these players can often have a greater upside.”

Kerr used Jared Polec - the Club’s first round selection (Pick No.5 overall) at the 2010 National Draft - as an example of how later-born players can take longer to develop.

“Jared was an absolute standout junior, but he was also one of the youngest players in that Draft (he was born in October) and it was reflected in his body size and shape,” Kerr said.

“We were aware of that, and always expected it might take a little bit longer for him to play regular senior AFL football.”

Polec is just one of many Lions draftees over the past three years to fit into this 'bottom-age' category, along with: Ryan Harwood (born in July), Sam Michael (July), Patrick Wearden (August), Josh Green (August), Josh Dyson (August), Ryan Lester (August), Claye Beams (September), Sam Docherty (October), Elliot Yeo (October), Mitch Golby (October), Jack Crisp (October) and Justin Clarke (November).

“It means that while we know we’re a young group, we’re actually a ‘young’ young group,” Kerr said.

“So it’s going to take them some time to develop the necessary stamina, strength and mental toughness required to withstand the rigours of four AFL quarters week-in, week-out.”

“Justin Clarke is a great case in point. His arrival at the Club seems to have coincided with a spurt of growth and physical maturity.”

“Since joining us in November, he’s put on 13kg and now looks like he’s got the body of a young man as opposed to a boy,” he said.

“His late birth and development has no doubt contributed to why he had little to no involvement with any elite talent pathways.”

Naturally young groups are also associated with inexperience, which is something the Lions will have in spades this Saturday night when the come up against Collingwood at the Gabba.

In fact, the Lions’ Round 7 team will be made up of seven players who have played less than 25 AFL matches, and 11 players with less than 50 games of senior experience.

In comparison, the Magpies will field a side with just three players with less than 25 games experience and only five with 50 matches or less.