London: England football great Gary Lineker led a host of sports stars expressing their anger at Britain's shock vote to leave the European Union on Friday.
On a practical level there was confusion over what the EU exit would mean for foreign players, not only in the lucrative English Premier League, but also in cricket and rugby union.
Sports lawyers say it is crucial that Britain negotiates successfully to remain part of Europe's single market, which enshrines freedom of movement.
Failure to do so could lead to an exodus of foreign talent and also restrictions on buying players.
Clubs could also lose the right to sign young players under the age of 18. At the moment, they can carry out such deals under a special arrangement between football world governing body FIFA and the EU.
Lineker, though, was more concerned about what impact the vote would have on his four sons.
'Ashamed of my generation':
The 55-year-old former Barcelona and England striker blasted the 50+ generation -- the majority of whom voted to leave -- for letting down the young.
"Feel ashamed of my generation," tweeted Lineker, whose middle name is Winston in honour of World War II leader Winston Churchill and whose birthday he shares.
"We've let down our children and their children," said Lineker.
"It's not a time for triumphalism. Not a time for division. Not a time for hatred. It's a time for change. A time for calm. A time in history."
Former Liverpool and England defender, and father of two, Jamie Carragher, a Champions League winner in 2005, also aimed his vitriol at the 50+ generation.
"A vote for (UKIP leader Nigel) Farage, (Leave figurehead) Boris (Johnson) & a recession, well done to the over 50s for thinking of the future!," tweeted the 38-year-old, who since retiring splits his time between TV punditry and charity work.
Northern Irish golf superstar Rory McIlroy cheekily suggested going back to January 1 and starting the whole year over again.
Northern Ireland was one of the few geographical regions -- London and Scotland being the other two -- where a majority of voters wished to remain.
"With #Brexit and the way the US presidential race is going.... Can we take a mulligan on 2016??," tweeted the 27-year-old four-time major champion, using the golfing term to retake a shot.
Foreign talent question mark:
In terms of the effect on foreign playing talent in English football, Football Association (FA) chairman Greg Dyke -- a pro-Remain campaigner -- said it would take a while to assess the impact.
"It could take two years to really know, but there could be quite an impact on English football because of Brexit," he said.
"It would be a shame if some of the great European players can't come here but I don't think that will happen. Whether the total number reduces will depend on the terms of the exit."
Dan Lowen, a partner at a leading specialist sports law firm, said staying in the single market was essential to ensure the Premier League remained competitive in the transfer market for foreign talent.
However, if at the end of the future negotiations over exiting the EU Britain did not succeed in remaining a member then all bets were off.
The extent of the impact "will be dependent in part on the terms of the renegotiated relationship with the EU. If we remain within the single market and accept freedom of movement as a result, the position may not change significantly.
"On the other hand, if there is no freedom of movement, it will be left to the UK government to determine the work permit rules that apply to players with EU citizenship."
