Once again as the summer transfer window rolls around, David de Gea is heavily linked with a move to Real Madrid.
The rumours have persistently cropped up season after season, but with Real Madrid now having hired the recently departed Spain coach Julen Lopetegui, interest is likely to only intensify this time around.
Lopetegui worked with de Gea in the national set-up, including throughout his stint as U21s coach between 2012 and 2014, and the two are believed to have a superb relationship.
Real Madrid thought they'd clinched the 27-year-old stopper's signature back in 2015, before a fax mishap at the final moment kept de Gea at Old Trafford.
The Spaniard, winner of Manchester United's player of the year in four of the last five seasons, is thought to be open to a move back to his home city, having previously represented Atletico.
If Real Madrid are to push hard and finally secure de Gea's signature this summer, could United look to Atletico once more for his replacement, and bring Jan Oblak to the club? And would the Slovenian actually be able to replace United's best player?
De Gea vs Oblak
Atletico Madrid have a stunning record of signing goalkeepers. Their last three first choice shot stoppers, Jan Oblak, Thibaut Courtois and de Gea himself, are all regarded as world class number ones that any club would want.
A comparison of their numbers yields interesting results.
Oblak has kept a remarkable 21 clean sheets in 34 La Liga appearances, the sort of record that would make Jose Mourinho lick his lips. De Gea, by contrast, kept 14 in 37.
This comes with the caveat, of course, that Oblak played behind an incredibly well drilled, mostly settled back four.
A goalkeeper's saves per goal ratio is a decent barometer of how good they've been - how many attempts have opposition forwards needed before managing to score against them? The roundly ridiculed Claudio Bravo went on a remarkable run of consecutive shots conceded in the 2016/17 season, but how do Oblak and De Gea's statistics compare?
De Gea's ratio of 3.46 saves per goal is impressive, especially when compared to Premier League adversaries Hugo Lloris (2.18) and Thibaut Courtois (2.10).
Jan Oblak's figure, on the other hand, is frankly unbelievable. His tally of 4.56 saves per goal proves that Atletico's outstanding clean sheets record isn't just purely down to a quality defence.
What has to be remembered is the sheer quality of some of de Gea's saves, showing cat-like reflexes on a number of occasions to save United's skin this season. Oblak's save stats would suggest that he could fit the bill as far as replacements go.
Catching and kicking
De Gea was much maligned early in his United career for his failure to cope with the physicality of the Premier League, but he has grown in stature remarkably throughout his time in England. He made 71 catches and just four punches compared to 65 and eight made by Courtois.
Oblak's numbers are comparable to De Gea's, having made 73 catches and five punches, albeit in three fewer games.
Again this would suggest that the Atletico stopper would fit the profile nicely to step into De Gea's shoes at United.
The United number one has always been known for the quality of his distribution. It is notable however, that he is asked to kick the ball further than his contemporaries, on average sending the ball 44 metres, eight more metres than Lloris and nine more than Courtois.
Understandably, this has influenced his kicking accuracy, standing at 63%. Whilst Lloris and Courtois' percentages are a lot higher, it is of more use to compare this percentage with Oblak, who, at an average of 42 metres, is asked to kick a similar distance to de Gea.
Oblak's kicking accuracy is lower than de Gea's, and at 55% is a figure that a lot of top managers would baulk at.
Jose Mourinho however, may not mind so much.
The best replacement
David de Gea has established himself as many people's pick as the best goalkeeper in the world and replacing that kind of quality is difficult.
Oblak's numbers stack up well and he is clearly a brilliant goalkeeper, but whether he could replicate the sheer quality of some of de Gea's more implausible saves remains to be seen.
If United are to sell to Real Madrid though, there aren't any better replacements available on the market than the Atletico Madrid stopper, who would seem a good fit.
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