Has it hindered them? Could it possibly have helped them?
And what about individual performance levels? Have you noticed any ‘crowd-pleasers’ going into their shells or can you spot an introvert seemingly revellling in the crowd-free environment?
Dr Maurice Duffy, a world renowned mindset and leadership coach, has written about Empty Stadium Syndrome and concludes that sport without crowds lacks in Gladiatorial behaviours and passion.
Duffy, who coached disgraced Australian cricket captain Steve Smith back from his ball tampering ban, also claims his research shows that games played without a crowd display 22% less emotional intensity.
"Performing in front of a crowd can be a great distraction to fatigue,” he writes.
"Sports people are natural performers and may suffer from a significant lack of energy during potential games without fans and they will have to address this issue by striving for more meaning and purpose from within.”
Duffy recently spoke to BBC Radio Newcastle about his findings...
You've looked into Empty Stadium Syndrome and how it affects players, what have you concluded?
I call it 'ghost games'. I see a lot of players playing with a zen-like quality.
What we find is that supportive crowds can positively affect a performance and we know that a hostile and critical crowd can have numerous negative implications.
But from looking at games in 2018, 2019 and around 190 games that were played behind closed doors what we discovered is that there are less emotional situations, there are less arguments, there are less interactions with opposing players, there is less advantage from the referee being a 'homer' and there is less intensity within the game itself.
It doesn't mean the players don't run more and it doesn't mean the players don't try as hard - there's just a lack of intensity.
What's the upshot of fewer emotional situations? Who benefits, who suffers and who is most likely to be successful in a game because of that?
It would be a generalisation to say who would benefit from that and who wouldn't but what you will find is that there are players that look very good during the week in training but on a Saturday in front of 55,000 people they just implode.
There are other individuals who don't and can't do it in training, who need the energy and the buzz, who need either the crowd on their back or for them and are dependent upon it and some of them just thrive off it.
I go back to Steve Smith and we talked about the Barmy Army and we used to through a preparation of listening to the songs that they were going to sing, so he thrived off the fact that they were singing at him and thrived off the fact they were hostile to him. In actual fact, the more hostility the more he knew he was getting through it.
Some players they want to do the tricks to show off to the crowd or they want to put that crunching tackle in to get the crowd on their side.
What you will notice in the games that I've studied, which was ten games over the two seasons, is that you can't blame the players for not trying, it's just that that extra ten per cent is just not there.
Even if you sit in a stadium right now during a game which I have done it's just an empty place. As someone who speaks in front of hundreds or thousands of people, when you get up on stage you get a buzz off that crowd. It's like standing on stage and nobody being there. It's a very boring place to be, energy just saps away.
How much is it down to personality type? Show-offs, as opposed to players who don't like the attention.
There are some players that will be enjoying it and what's going to be interesting is the transition back to crowds, and adjusting to the mentality that's going to be needed to deal with crowds again.
Some players will have become accustomed to it. Some players will have come into the team.
Take the Liverpool game when they trailed Barcelona 3-0 in the Champions League in 2019. Before the game Liverpool talked about their twelfth man and Barcelona talked about the Anfield crowd. What we found was that the more the crowd shouted and booed Barcelona started making more basic mistakes and innacurate passes and started taking poor touches.
Looking at this situation, I'll talk about the emotional aspect of it, the instensity, the determination and the fact it feels like a ghost game. It's not just in football, it's also in rugby, cricket and even in golf.
I coach some top class players who are playing with no crowds right now and they're telling me how they find it so difficult to perform because it just feels like a practice game.
When fans can return will they be much more appreciated than they have been in the past?
I think so, because what we see from looking at the games is that there's a home advantage, no doubt. We call it confirmation bias.
A referee, dependent on the volume of the crowd, is more likely to go with the crowd than to go against it, and is more likely to make a decision on behalf of the crowd.
Referees are very professional and I know they are trained for it and I'm sure they will say there are no biases but the stats show that home advantage is critical in the way that referees tend to referee matches. It's also critical in the way that players tend to play in matches.
The stadium does have an impact and I bet a lot of the players will really appreciate it when the fans are back and a lot of us will appreciate the impact fans have in sport as well.
In conclusion, what impact is Empty Stadium Syndrome having on performance?
When you talk about home advantage you tend to talk about familiarity, less stress, a greater understanding of the crowd and the support. When you strip those things away it has a mental impact upon any individual.
If I look at performane in business, and a lot of people are feeling stressed in business, a lot of people are bored with the isolation and a lot of people are fearful about it.
We have a 20-30% increase in the number of people having mental problems or they're having relationship problems. And players are not immune from that.
So they're peforming in an environment that's alien to them within a broader environment that's difficult for them in circumstances where they are no different from us and they have all of the same hassles as we have with home schooling etc etc.
So it's no wonder we've seen performance dip in business, we've seen productivity dip in business and we're also seeing the same thing in sports.
It affects everyone’s performance. We cannot divorce football from the greater social environment right now, so you have the empty stadium syndrome which is alien to them but you also have the wider environment.
I coach hundreds of people and there are very few of them that don’t have some kind of problems at home, and footballers are the same.
At the moment they’re not going into a familiar working environment and they’re finding that difficult as well.
Visit mauriceduffy.com for more information and to read his blog on Empty Stadium Syndrome.