One could argue Manchester United have still not recovered from the departure of the great Alex Ferguson.
Ferguson quit after leading United to the 2012-13 Premier League title, the 13th of his reign and their 20th in total. He won the Champions League twice, too.
United have toiled in the intervening years, unable to replace one of sport's all-time finest leaders.
The announcement of Ferguson's exit came on May 8, 2013, allowing us to reflect on that news among other notable sporting events on this day.
2004 - Controversy as Marquez makes recovery
Few boxers are able to recover from the sort of first-round barrage Manny Pacquiao inflicted upon Juan Manuel Marquez in their 2004 featherweight title fight.
And, as it turned out, Marquez should not have been able to either.
The Mexican was sent to the canvas three times before the first round was up and, although he subsequently outboxed Pacquiao, Marquez would have narrowly lost but for a scoring error.
Burt Clements judged the bout 113-113, prompting a draw as Guy Jutras and John Stewart went 115-110 each way. But Clements scored the opening round 10-7 to Pacquiao, rather than 10-6, and later acknowledged: "I screwed up."
Pacquiao had to wait almost four years to defeat Marquez - again by split decision - before another disputed verdict went in his favour in 2011. A year later in their fourth encounter, Marquez took the judges out of the equation with a brutal sixth-round knockout of his great rival.
2013 - Ferguson leaves a champion
Having suffered final-day pain at the hands of rivals Manchester City in 2011-12, Ferguson made sure to bow out on a high with the 2012-13 Premier League crown.
After 26 years at the helm, the Scot confirmed his departure on May 8 - this time not backtracking on this decision as he had in 2001.
David Moyes and Jose Mourinho were among the early favourites to replace Ferguson, with the former appointed on the outgoing manager's recommendation.
Moyes' stint was short and unsuccessful, though, and neither Louis van Gaal, Mourinho nor now Ole Gunnar Solskjaer have been able to add to United's tally of 20 top-flight championships.
2014 - Beckham and Donald arrive in NFL
It is six years since some of the most prominent names in the NFL were drafted, with Odell Beckham Jr and Aaron Donald both selected in 2014.
Beckham went to the New York Giants with the 12th pick, establishing himself as a star at wide receiver before moving on to the Cleveland Browns last year.
Donald is now a two-time Defensive Player of the Year but then followed one pick after Beckham, going to the St Louis Rams. Khalil Mack was another standout at number five.
But the first overall pick was used by the Houston Texans to secure Jadeveon Clowney. Traded to the Seattle Seahawks in 2019, the defensive end is now a free agent looking to put persistent injury troubles behind him.
2019 - Another Champions League classic
Just 24 hours after Liverpool stunned Barcelona with a 4-3 aggregate semi-final win, the 2018-19 Champions League was at it again.
Tottenham looked down and out when Matthijs de Ligt and Hakim Ziyech netted for Ajax to add to their 1-0 first-leg lead, with Mauricio Pochettino's men needing three goals in Amsterdam.
However, Lucas Moura netted twice in the space of five second-half minutes, and Spurs kept pushing deep into stoppage time.
With 96 minutes on the clock, Moura struck once more to seal his hat-trick and Tottenham's place alongside Liverpool in the final, leaving a previously inspired young Ajax side bruised and beaten on the turf.