What was there about Delpo, that Federer lost 4 finals to him?

[Break To Win]

I can't understand why Roger lost so many times, especially in finals to Del Potro. Fed had several weapons to defeat the Argentinian, and all their variety such as slices, drop-shots, volleys.

I believe that in the US Open final, Fed underestimated Delpo. But after this final, he shouldn't lose to other finals, especially Indian Wells 2018.

 

[BeatlesFan]

2009 USO loss still stings. The general consensus with these losses is that Fed was stubborn and refused to avoid Del Po's FH. This was clearly true in 2009, and it's still baffling why he did this. Ego? Trying to prove he was so mighty that he doesn't need to avoid an opponent's best shot?

The 2018 IW final was another ridiculously terrible loss. He blew three match points.

 

[BauerAlmeida]

Del Potro could take the initiative which is something not many players could do against Fed. Federer himself mentioned that his sheer power in the serve and forehand was something that bothered him when playing against him.

 

[Mainad]

I believe the 2009 US Open final was the most painful loss in Federer's career (or maybe 2nd to 2008 Wimbledon). He had been unbeaten in US Open finals for the previous 5 years and surely did not expect to lose to the likes of Del Potro who had not yet established himself as a major contender in Slams. I recall how increasingly bad tempered he became as the momentum of the match began to swing against him (arguing with the umpire etc.). After that loss he made only 1 other final there (6 years later which he lost to Djokovic). Del Potro had permanently ended Federer's winning streak at the US Open.

It's interesting that they met 3 times in the final of Fed's home tournament in Basel (2012-13,2017) with Del Potro winning the first 2. There were certainly times when it seemed he had Fed's number!

 

[JasonZ]

I believe the 2009 US Open final was the most painful loss in Federer's career (or maybe 2nd to 2008 Wimbledon). He had been unbeaten in US Open finals for the previous 5 years and surely did not expect to lose to the likes of Del Potro who had not yet established himself as a major contender in Slams. I recall how increasingly bad tempered he became as the momentum of the match began to swing against him (arguing with the umpire etc.). After that loss he made only 1 other final there (6 years later which he lost to Djokovic). Del Potro had permanently ended Federer's winning streak at the US Open.

It's interesting that they met 3 times in the final of Fed's home tournament in Basel (2012-13,2017) with Del Potro winning the first 2. There were certainly times when it seemed he had Fed's number!

2019 wimby is his most bitter loss, then the 2009 uso loss. the other bitter losses he avenged multiple times