Roy Keane has credited Jose Mourinho with 'raising the bar' in the Barclays Premier League to catch the big guns napping.
The Sunderland boss, currently making his way in the management game, saw the Portuguese drag Chelsea from the ranks of the pretenders to the pinnacle of the domestic game as his former club Manchester United and Arsenal were muscled aside.
Keane believes Mourinho's departure from Stamford Bridge yesterday has left a huge gap, but he is confident one of the most colourful characters in the modern game will be back in business before very long.
Keane said: 'I have never come across him, but I just look at what he brought to the Premier League, and he raised the bar.
'He raised the bar for everybody, even for the likes of United, the Arsenals, they had to liven up their act a bit, and they came back stronger again, United and Arsenal, in the last year or two.
'Jose Mourinho definitely did that for the Premier League, and he did the biggest challenge, where he turned a very good Chelsea team into a top team. That's the biggest step and the hardest step.
'There are lots of good teams out there - I could name you 10 and say, 'they are a good team' - but they are not a top team, and that is the gap he bridged.
'He will be a loss to the Premier League, there is no getting away from that.
'The big thing for me is that he raised the bar for everybody because maybe one or two people took their eye off the ball and he came along and thought, 'I am the real deal', and that was good to see.
'But I am not sitting here feeling sorry for him, far from it. He has proved to be a top manager and he will continue to be a top manager, it's just unfortunate it won't be at Chelsea.'