Tournament director Gilbert Ysern explained that while he could have opted to ignore the rankings - and even contemplated doing so, because Nadal is "the best player on clay" and Roland Garros "is a bit like his garden" - there wasn't a consensus it was the proper thing to do.
"You can understand the argument that those who are higher than him in the rankings in a certain way deserve their ranking," Ysern said, "and to move these players back to move Nadal forward could have been considered unfair."
Nadal, for his part, did not sound too fussed about the matter, saying, "I had a very good chance to be No. 10 (given the time off), and there are lots of chances to be worse, and I accept the situation."
So last year's French Open runner-up to Nadal, Novak Djokovic, will be seeded No. 1, and 17-time major champion Roger Federer will be seeded No. 2.
Djokovic handed Nadal one of his two losses of 2013, in the Monte Carlo final on clay last month, proof that Nadal is not completely invincible, even on the slow surface he dominates.
The No. 1-ranked Williams, meanwhile, has been unbeatable lately. She arrives in Paris having won a career-high 24 consecutive matches and is 36-2 with a tour-leading five titles this season. That's part of a stretch in which she's gone 67-3, including titles last year at Wimbledon, the U.S. Open and the London Olympics.
That 70-match stretch of excellence dates, probably not coincidentally, to her last match at Roland Garros, a shocking loss to 111th-ranked Virginie Razzano of France in the first round in 2012. It is her only opening loss in 50 career Grand Slam tournaments - precisely the sort of thing that seems to happen around these parts.
While there certainly are other women who realistically can harbor hopes of lifting the trophy in a little more than two weeks - defending champion Maria Sharapova is the best example - Williams appears to be playing as well as ever at the moment.
She already owns 15 Grand Slam singles titles, but the French Open is the only major tournament she's won fewer than four times. Her lone championship in Paris came in 2002.
"Nothing is ever perfect and I learned that last year when I felt perfect," Williams said. "So I am still in a danger zone."