Federer back as Nadal seeks ninth Monte Carlo title
Switzerland's Roger Federer celebrates after beating Kazakhstan's Andrey Golubev during the Davis Cup World Group quarter-final match Switzerland vs Kazakhstan on April 6, 2014 in Geneva - by Fabrice Coffrini
Federer, his season taking flight and his ranking back to a more-than-respectable world number four, last competed at the optional Masters in 2011, when he was shuttled out in a quarter-final surprise by Austrian Jurgen Melzer.
The 32-year-old Swiss who lost three straight finals here to Nadal between 2006 and 2008, will hope for the kind of week which Novak Djokovic produced a year ago.
The Serb defeated Nadal for the title 12 months ago, meting out to the Spaniard only his second loss at the tournament since first playing it as a 16-year-old in 2003.
Federer made the decision to play after helping Switzerland into the Davis Cup semi-finals last weekend, a boost to his rising confidence.
He opens after a bye in the second round against the winner from the veteran pair of Radek Stepanek and Ivo Karlovic.
Nadal is starting his huge spring task of defending four 2013 titles on his surface of choice, with the Spaniard winning Barcelona, Madrid, Rome and an eighth trophy at Roland Garros.
After losing the Miami final a fortnight ago to arch rival Djokovic, Spain's world number one finds himself back in his tennis comfort zone at precisely the right moment, with the top seed opening against either a qualifier or Frenchman Gilles Simon.
And with all the pressure on his game for the next two months on the dirt, Nadal needs to keep his confidence sky-high.
"I'm now at the top of the (points) race arriving to the clay court season," he said.
"That's positive for me, but I need to be my 100 per cent. To make a difference I need to try to be aggressive, to try to move myself very well on clay, and to try to find the best feeling possible as soon as possible."
Monte Carlo-based Djokovic takes the second seeding as he defends the title and should be well-rested after a few weeks of downtime since Miami.
Swiss Stanislas Wawrinka takes the third seeding, with the Australian Open champion trying to find his psychological balance as the enormity of his Melbourne title win over Nadal takes time to sink in.
He will play either Marin Cilic or Fernando Verdasco.
Federer is seeded fourth ahead of Czech Tomas Berdych and number six Spaniard David Ferrer.
Missing from the field is Argentine Juan Martin del Potro, who is healing from right wrist surgery, while Andy Murray has opted to stay as far away from the clay as possible until absolutely forced to go on it, the Scot will not take his chances until Madrid in three weeks.
The forecast seventh seed, France's Richard Gasquet, pulled out of the event on Saturday with a back problem.