Raheem Sterling will sit out of England's Euro 2020 qualifier on Thursday after a bust-up with international team-mate Joe Gomez. (More Football News)
Sterling admitted his emotions got the better of him when he confronted Gomez, after the pair also clashed on the field during Liverpool's 3-1 win over Manchester City on Sunday.
Gareth Southgate has sought to act quickly and decisively to draw a line under the matter, but the England manager can at least take comfort from the fact he is far from the first boss to have to try to defuse a team-mates' tiff.
Here we look through some examples of when presumed footballing friends became – however briefly – the best of enemies.
Neymar v Nelson Semedo
Neymar's world-record move to Paris Saint-Germain dominated Barcelona's preparation for the 2017-18 season, and all was not well on the training ground in the weeks leading up to the €222million switch.
Recent arrival Nelson Semedo became involved in a skirmish with the wantaway star in what proved to be an unseemly coda to his time at Camp Nou.
"I just arrived and one of the most important players in the team got in a fight with me," Semedo told Sport five months on from the July 2017 fracas. "It annoyed me at the time, but I also understood he was in a difficult moment, he wanted to leave."
Zlatan Ibrahimovic v Oguchi Onyewu
Never a shrinking violet, Zlatan Ibrahimovic boasts a career of confrontation in football. The taekwondo black-belt seemingly came close to meeting his match in USA defender Oguchi Onyewu when both played for AC Milan.
"I head-butted him, and we flew at each other," Ibrahimovic wrote in his autobiography. "We wanted to tear each other limb from limb. It was brutal. We were rolling around, punching and kneeing each other. We were crazy and furious – it was like life and death.
David Beckham v Alex Ferguson
Many a Manchester United player felt the heat of Alex Ferguson's infamous 'hairdryer' during the Scot's historic Old Trafford reign but – as far as we're aware – his ferocious words never actually drew blood.
The same could not be said for a stray boot in the United dressing room, though, when David Beckham was given a rocket by his boss in the aftermath of a February 2003 FA Cup defeat to Arsenal during the midfielder's final season at the club.
"He was around 12 feet from me. Between us on the floor lay a row of boots. David swore. I moved towards him and, as I approached, I kicked a boot. It hit him right above the eye," Ferguson explained. The resulting cut and butterfly plaster predictably dominated as the UK tabloids gorged on the fallout.
Mario Balotelli v Micah Richards
Mario Balotelli was rarely far away from behind-the-scenes controversy at Manchester City, allegedly throwing darts at youth team players and once even grappling with his manager and mentor Roberto Mancini.
However, things reached boiling point in 2011 due to the unexpected multi-lingual talents of one of his team-mates.
"We were playing five-a-side and we were losing because he didn't work, which is evident,' Micah Richards told Sky quiz show 'A League of Their Own' in 2016. "He swore at me in Italian and he thought I didn't understand. But I know a bit of Italian lingo, so I said, 'Who you talking to?' He said it again, so we squared up and I offered him out. But he said no."
Craig Bellamy v John Arne Riise
Balotelli's arrival at City in August 2010 came around the same time as Craig Bellamy was tying up a loan move to Cardiff City, leaving us all to wonder what might have happened had the combustible duo shared a dressing room for any period of time. John Arne Riise, perhaps, has a fair idea.
In an infamous incident before a Champions League game at Barcelona in 2007, where both players went on to score in a Liverpool win, Riise drew Bellamy's terrifying wrath when he refused demands to sing karaoke on a team night out.
Later on, Riise found an unexpected visitor in his hotel room. "Craig Bellamy at the foot of my bed with a golf club in his hands," he reported in his autobiography. According to the Norway full-back's version of events, he managed to avoid Bellamy striking his shins by jumping out of bed but took blows to his hip and thigh.
Aboubakar Kamara v Aleksandar Mitrovic
While the risks of a rowdy team karaoke session might seem obvious in hindsight, sometimes even yoga isn't safe.
Aboubakar Kamara had not appeared particularly zen when he grabbed the ball off Aleksandar Mitrovic to take and miss a penalty during Fulham's December 2018 Premier League game against Huddersfield Town.
A fight then reportedly broke out between the pair at a yoga session and an eventful few weeks for Kamara concluded with him being arrested on suspicion of actual bodily harm and criminal damage after an incident at Fulham's training ground.
Alan Shearer v Keith Gillespie
Famously incisive in front of goal, the Premier League's all-time record goalscorer Alan Shearer once became involved in an argument about dropped cutlery with Newcastle United team-mate Keith Gillespie that escalated sharply.
"We ended up going outside, and I took one swing and missed, and he hit me - and that was goodnight," Gillespie told talkSPORT of the scrap during a 1997 team trip to Dublin. "I did actually spend a night in hospital. Because when he hit me, I fell and hit my head on a plant pot. I was unconscious."
Apparently, Shearer visited his stricken team-mate and they "had a laugh about it". They weren't the only ones.
Stig Tofting v Jasper Gronkjaer
A tough-tackling midfield enforcer, you might expect any training ground row featuring Stig Tofting to have followed a bone-crunching challenge. However, there was more shivering than shuddering when a pre-2002 World Cup jape involving Jasper Gronkjaer got out of hand.
During some stretching exercises, Tofting and partner-in-crime Thomas Gravesen sprayed the then-Chelsea winger with water bottles and put ice cubes down his shorts. Gronkjaer hurt his eye during the prank, which concluded with him wrestling Tofting and being grabbed by the throat.
Danish FA official Jim Stjerne-Hansen told reporters: "These players need a kindergarten teacher to sort them out."
