Clubs in the upper echelons of English football tend to have fairly common reasons for player absences - it could be injuries, suspensions or international commitments that prevent players turning out for the top clubs.
Down at Exeter City in League Two, however, the situation is somewhat different. The Grecians face losing the regular services of one of their key players so far this season because he has gone back to school.
There has been a buzz around Ethan Ampadu at St James Park for a while. The son of former City midfielder Kwame, Ampadu Jnr has regularly played up the age groups for the club's youth teams and is the subject of an international tug-of-war between Wales and England for his services. He has represented both countries at youth level, and was even pictured training with the Welsh senior team in the build-up to their successful European Championships campaign over the summer.
The youngster featured in pre-season friendlies for Exeter, but there was still widespread surprise when Paul Tisdale named the 15-year old in his starting XI for the EFL Cup tie at home to Brentford in August. Many City fans had not expected to see Ampadu feature in the first team at all, but were soon grateful that they had been given the opportunity to do so.
Playing out of position at centre-back - Ampadu is more widely known as a central midfielder - he slotted in effortlessly to the back four and brought a sense of calm and class that belied his 15 years. Indeed, Tisdale commented after the game, as reported by the BBC, that Ampadu had played more like a 35-year-old, so assured was his display.
Exeter City manager Paul Tisdale
Having been deservedly named Man of the Match on his debut - no mean feat playing against a team from two divisions above - Ampadu has featured in every Exeter squad since then, including most notably the match against Hull City. Lining up against Premier League opposition, Ampadu did not look out of place and was again named the star man as the Grecians slipped to a 3-1 defeat.
While most lads his age may have spent the last weekend of the school holidays rushing round Clarks looking for shoes or having a kickabout at the park, Ampadu was handed his first away start for the Grecians on Saturday at Colchester in a 3-2 win which saw them climb out the bottom two.
Naturally, such impressive performances at such a young age have not gone unnoticed, with vultures from higher divisions already circling. Ampadu's father is an academy coach at Arsenal, who are just one of several Premier League clubs who have been linked with making a move for the prodigy by Goal.com - a list which also includes Manchester United.
However, Ampadu would do well to look at the other young talent that Exeter have produced in recent years before making a decision on his future. Matt Grimes left the Devon club for Swansea for £1.75m after a string of highly impressive performances over the course of 18 months at Exeter, but has played just a handful of games for the Welsh side and currently finds himself frozen out just a month into a loan spell at Leeds.
Matt Grimes, who left Exeter City for £1.75m in January 2015
Sean Goss, meanwhile, was just 16 when he was snapped up by Manchester United in 2012 before featuring for City's first team. Whilst reports suggest he has performed well for United's u-21 side it seems unlikely that he will get a chance in the club's starting XI anytime soon, particularly given Jose Mourinho's notoriously indifferent attitude to developing young players.
Tisdale has praised Ampadu's school on the club's website for their handling of the youngster, and it is to the manager's credit that he has phased the youngster in to his plans gradually. No Exeter fan is expecting Ampadu to deal with the physical world of League Two on a weekly basis, but for now staying put is his best option if he wants regular competitive football.
So what would Arsenal or Manchester United be getting were they to make a move for Ampadu? As someone whose hairstyle makes him instantly noticeable on the pitch there is no hiding place for the youngster, and it seems he thrives on the responsibility. He is happy to come short and receive the ball from the goalkeeper to start attacks from the back, and the quality of his longer passes have pleasantly surprised Exeter fans who have become used to such attempts finding either the head of an opposing centre-back or Row Z of the nearest stand.
Sean Goss - another from the Exeter City conveyor belt - in action for Manchester United's U21 team
It seems inevitable that Ampadu will eventually take his place in the centre of midfield, with perhaps only the physical aspect of being in the League Two engine room preventing Tisdale from playing his young starlet there already. He doesn't shirk a challenge, however, and is comfortable in the air - his debut against Brentford saw him suffer a clash of heads which could have seriously harmed someone with a more standard haircut.
How many times Ampadu features for Exeter this season will depend on his school commitments as well as the form of the team - he has so far benefited from an injury crisis and may not have got his chance had everyone been fit. However, his promising early performances have established Ampadu as part of the first team furniture with the Grecians, with City fans almost certainly preparing their 'I was there...' tales to regale others with if the 15-year old does make the expected step up the pyramid before too long.
His performances have also got fans talking on Twitter, as seen below:
Ethan Ampadu getting expelled from school would be the greatest signing in the clubs history.— Ethan Ampadon't (@cornwallmorris) September 3, 2016
Exeter City Football Club
15 year old Ethan Ampadu, capped by England and Wales at youth level, made another strong appearance for #ECFC. Came away with MotM.— aidan (@englandyouth) August 24, 2016
First time seeing Ethan Ampadu play, only 15 years old and MOTM Vs Championship and Prem opposition.. Plays with no fear #ECFC— Jamie (@JamieEcfc) August 23, 2016
Ethan Ampadu looks quite comfortable against premiership opposition.— Paul ECFC Sussex (@Paul_not_ecfc) August 23, 2016
My first game of the season, last night. Bit harsh to boo a patched up team. I was well impressed, with Ethan Ampadu. A class act. #ECFC— JJ from Somerset (@ECFCJJ) August 17, 2016