The Japan Rugby Football Union named a 40-man Rugby World Cup training squad Wednesday, the day after the nation marked 500 days to go until the tournament kicks off in Tokyo.

Masahiro Kunda, director of the Japan national team, said in a press release the squad would likely change over time depending on the form of players. Special attention is being paid to fitness to account for the strain of players competing in both Super Rugby and the Japan Top League.

"Originally, we planned to announce this first training squad at the conclusion of last year's November tests in France. But in consultation with head coach Jamie Joseph, we thought it was best to consider the physical condition of Super Rugby players and wait for the results from various measures. For that reason, we believe this is the best time to make the announcement," the former Japan hooker said.

The squad contains nine players who played in Japan's historic win over South Africa at Rugby World Cup 2015: Keita Inagaki, Masataka Mikami, Shota Horie, Shinya Makabe, Amanaki Lelei Mafi, Michael Leitch, Fumiaki Tanaka, Yu Tamura, Harumichi Tatekawa and Akihito Yamada.

There are five uncapped players in the squad, all forwards, in Grant Hattingh, James Moore, Ben Gunter, Masakatsu Nishikawa and Pieter "Lappies" Labuschagne, with Kunda verifying that "players who are not yet eligible to play for Japan but might be able to achieve eligibility in time to play for the national team at the World Cup have been included."

Youth is recognized in the form of Koo Ji Won, Kazuki Himeno, Ryuji Noguchi and Rikiya Matsuda, while three Rio Olympians are included in Yoshitaka Tokunaga, Kenki Fukuoka and Lomano Lava Lemeki.

One notable omission is flyhalf Takuya Yamasawa, who underwent shoulder surgery earlier this year after spending some time in New Zealand with the Crusaders development squad.

"It is expected that the players in the training squad will change, and we expect to announce the second training squad at the conclusion of the (current) Super Rugby season," Kunda said.

Looking ahead, the former Toshiba Brave Lupus head coach said, "It is possible that players will enter and leave the training squad based on their performance in tests, in Super Rugby and in the Top League. We believe that players not currently named to the squad will work hard and prepare."

"Now that we have reached the 500-day mark prior to the Opening Game of Rugby World Cup 2019, we are grateful for the continued cooperation of every team in the Japan Rugby Top League as we place priority on our national team strengthening program. With the full attention paid by the teams to player welfare (by providing sufficient time for rest and reconditioning), we expect to become even stronger as we head toward Rugby World Cup 2019."

(Pair of official mascots for the 2019 Rugby World Cup)

The Brave Blossoms play Italy on June 9 and 16 in Oita and Kobe, respectively, before taking on Georgia on June 23 in Toyota City.

A source at the JRFU said the squad for those games will be announced during the week beginning May 21.