Nadal will face Dominic Thiem in the quarter-finals, while Djokovic will take on Del Potro.
Mark Petchey says the summer season can help inspire a revival from the world number one.
World number one Andy Murray has won just one title thus far in 2017.
Federer will be skipping the entire clay court swing of the season for the first time since he turned pro in 1998.
World number two responds to the news that the 18-time major champion will miss the clay court showcase.
Nadal ended his seven match losing streak to the Serb with his recent win in Madrid.
Nadal is seen as the favourite to emerge victorious at Roland Garros.
The 18-time major champion's withdrawal from Roland Garros not a surprise says Australian doubles legend.
Nadal has won three titles back-to-back to rise to world number four in the ATP rankings.
Federer and Nadal's form have seen them climb back into the top five of the world rankings.
Novak Djokovic has made the semi-finals just once in five tournaments since his win in Doha in January.
Federer is skipping the 2017 Italian Open, which began on 14 May.
The win is Nadal's third title of the calendar year and his 30th Masters 1000 title.
Djokovic lost to Nadal for the first time in three years.
Nadal is looking for his third title of 2017 after wins in Monte-Carlo and Barcelona.
Nadal ended a seven-match losing run against the former world number one.
Nadal has made 5 finals and won 2 titles thus far in 2017.
Wawrinka expects Djokovic to win Grand Slams again.
Nadal defeated Nick Kyrgios comfortably 6-3, 6-1 while Murray suffered defeat yet again.
Spanish number three believes evergreen Federer is the man to beat in Paris.
Federer has won three of the four tournaments he has played in 2017.
Nadal defeated Fabio Fognini 7-6, 3-6, 6-4 in the second round in Madrid.