Isolation, boredom, loneliness and anxiety. During 12 months of living with social restrictions -- with all UK residents forced to remain home except for work, school or essential activities -- as a result of the COVID-19 pandemic, few people will have been untouched by those states of mind. Even highly paid footballers are battling both the physical constraints and the emotional toll.
"I know one player whose dad was very ill and he wasn't sure if he would be able to see him again, so he asked me if he should just go and not tell the club," a member of a Premier League club's player care team told ESPN. "That puts me in a tough situation because I am employed by the club, but how can I sit there and tell him he shouldn't do it?
"I could be the best player liaison officer in the world, but you can't replicate being someone's mum, dad or partner."
Behind the curtain of Premier League glamour, top footballers are facing many of the same challenges as everyone else, but for those players living in an unfamiliar country with families on the other side of the world, this international break may prove more of an ordeal than an opportunity to recharge.
Europe begins World Cup qualifying this week, though with lockdown measures still in place in the UK and across the continent restricting international travel without quarantine periods. It means that a chance to return home, catch up with family and simply enjoy a change of scenery has been denied to many players, even those not involved with their national teams.
Most notably, the large contingent of South American stars, whose World Cup qualifiers have been postponed due to travel restrictions to and from Europe, are stuck away from home. The example above, of a player torn over whether to remain in England and adhere to COVID-19 protocols, or to find a way to fly home to visit a dying parent, is perhaps an extreme example of the challenges some players are having to overcome, but it is not a unique scenario.
Liverpool goalkeeper Alisson Becker chose not to return to Brazil last month, due to the prospect of a 10-day quarantine period at both ends of the trip following the death of his father in a swimming accident. Jurgen Klopp, the Liverpool manager, was also forced to remain in the UK and miss the funeral of his mother because of travel restrictions between England and Germany. David de Gea, meanwhile, was given compassionate leave by Manchester United to return to Spain for the birth of his first child, but the goalkeeper was forced to isolate on his return to England and has now lost his first-team spot -- at least temporarily -- to Dean Henderson because of his prolonged absence.
Tom Young, a performance psychologist who has worked with the Belgium national team and leading golfer Tommy Fleetwood, says that players who are unable to link-up with their countries during this international break will suffer a psychological toll as a consequence.
"Joining up with the national team can offer an escape from the domestic season and an opportunity to connect with teammates who they may well have known since childhood," Young told ESPN. "The mental health benefits are significant. But arguably the greater psychological impact will come from players being unable to return home to see friends and families.
"That isolation, footballer or not, can impact on our well-being. This is where proactive support from the club and teammates is crucial."
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To that point, Angelino, RB Leipzig's Spanish defender, admitted recently that he's struggling with the inability to make the short trip between Germany and Spain to see his young child.
"The worst part of all this, being a foreigner, is not seeing the family," Angelino told The Independent. "My son is not here [in Germany] and I obviously want to see him more. It's a bad situation, so I prefer not to speak about it. Not seeing the family is the most important thing at the end.
"The outside part is the worst side when you live abroad. You have to deal not being able to go home, or people coming in whenever you want. I would say the only good thing is playing games: I'm happy when we play three games a week because you don't think about this that much."
For those club employees tasked with ensuring that footballers are happy and settled away from the club environment, the pandemic has made it impossible to use tried-and-tested methods when it comes to accelerating the settling-in process for players and their families.
"It's really tough," the player care officer said. "You'd normally suggest they would meet up with the family of a player from the same country, or same language, go for dinner with the family etc. Social events, too -- the South American players often group together for barbecues, but you can't do that now.
"At games, you'd have the players lounge where families would get together, the kids would play and it would help the new players bond and settle in, but again, that isn't allowed because of COVID-19 so it makes it more difficult.
"At the outset, in March 2020, we had to keep all the players in the country because we didn't know whether we would be playing again in three weeks or three months. But we had a number of foreign players, living in flats on their own, who were basically alone for three months -- we couldn't see them, go to check on them, so that was really tough."
Even during the summer, following the delayed conclusion to the 2019-20 season, travel restrictions imposed by the UK on Spain and France -- at the time, there was a mandatory 14-day quarantine period for people flying in from those countries, since reduced to 10 days -- denied many players the opportunity to return home before the start of an abbreviated preseason training.
"A lot of the European players were seeing their countries being ravaged [by COVID-19] but were unable to go home to be with their families, and that was a really hard time for them," the player liaison officer said. "The summer break wasn't long enough for them to go home, come back and then isolate for two weeks.
"We have tried to support players as best as we can, but after a year of this, there are definitely players in a bad mental health space who wouldn't normally be."
There is a flip side, however. One player agent told ESPN that while his clients have broadly found it difficult being unable to see friends and family back home, they've also enjoyed being able to rest without the usual daily distractions of life.
"They know they are lucky," the agent said. "They have been able to stay busy, playing three games a week, and the competitive element of their job allows them to feel more alive than the average person in lockdown."
Young, the performance psychologist, agrees with that perspective, but he says that while some players and teams will find positives from the unique circumstances of the past 12 months, it is the athlete's family that will still have difficulties and those stresses ultimately bounce back to the player.
"On one hand, new signings have gone through a unique period of time with their new teammates," he said. "They've shared a period of history and will form lasting bonds. It's the life away from the club that will bring more challenges. Relationships give a sense of belonging. The player can develop these at the club, but family members can struggle to do the same. Players and their families adapting to a new language and country is testing at the best of times, but throw in the emotion and isolation of a pandemic, along with the pressure of elite sport, and it can undoubtedly be pretty intense.
"'Player first, athlete second' is something we hear people talk about. Some players are able to block personal issues out when they [step on to the pitch], but as a general rule, the happier a player's life is away from the field, the more likely they will be to perform on it."
With European players able to travel and join up with their national squads this week, many clubs have an unusually large contingent of South American and African players confined and in need of a training routine when staff usually relish the opportunity, during the four international breaks in every FIFA calendar, to enjoy much-needed down-time. But there is also a sense of relief within clubs that many players won't be travelling beyond Europe. Throughout this season, COVID-19 infection rates have risen within football after each international break, prompting Manchester City manager Pep Guardiola to warn last month that "the moment you start taking planes and go places, everything can happen."
"Earlier this season, we had players representing the smaller nations and they would fly back on EasyJet, with the general public, and walk straight back into the training ground," the player care officer said. "If you are sending a player away with a major national team, you know they have the resources to deal with the protocols properly, but you just don't know how stringent the measures are. We would have players testing positive, getting sick and ending up stuck in the country they were playing in, so how do we get them home?
"On one occasion, our club tried to get other teams to contribute to a private plane to get all tested players back from a game in Europe, but we couldn't get the agreement, so they would fly back with British Airways, Easyjet or whoever, and then you would get all the positive tests."
With international travel having almost ground to a halt in the early months of 2021, such loopholes are unlikely to appear during this international break, potentially sparing football from another spike in infections. But for those players stuck in a foreign country, unable to see friends and family back home, this will be a very long, and sometimes lonely, two weeks.