Jose Mourinho is set to be appointed as Manchester United boss, The BBC report, and the manager will be keen to learn from his mistakes at Chelsea which culminated in his firing last year.
Perhaps the biggest error, on reflection 12 months on, was his decision to snub the opportunity to sign Toby Alderweireld when Atletico Madrid had pushed him in their direction.
The Telegraph reported last May: "Chelsea are keeping Atlético Madrid waiting on their offer to swap Toby Alderweireld for Filipe Luis with manager Jose Mourinho prioritising alternative defensive transfer targets."
The report explained Mourinho set his sights on Raphael Varane and John Stones instead, but was unsuccessful with his offers for the duo, with the saga relating to the Everton defender dragging on right up until deadline day.
Chelsea struggled badly defensively at the start of the campaign, with Mourinho appearing to lose faith in club captain John Terry.
Alderweireld would have been a cheaper option to either Varane or Stones, and importantly he was available when the others were not.
Mourinho ended up selling Filipe Luis to Atletico anyway, while Alderweireld went on to join Tottenham Hotspur where he enjoyed an outstanding season, voted by his peers into the PFA Team of the Season.
Rejecting the chance to sign Alderweireld may have been Mourinho's biggest mistake as manager, and had he bought the Belgian, it might just have helped him avoid the sack.