Japan coach Jamie Joseph opted against making wholesale changes Thursday as he named his side to play Tonga in the second round of the Pacific Nations Cup.

Michael Leitch will lead a side on Saturday at Hanazono Rugby Stadium that shows just five changes from the XV that started last week's 34-21 win over Fiji in Kamaishi, Iwate Prefecture.

Asked why he had avoided moves which could give fringe players a chance to impress before the Rugby World Cup kicks off in 50 days, Joseph indicated he had a reasonably clear picture of the final squad for the tournament to be named at the end of the month.

"My thinking is I have prepared a team for the World Cup, no more, no less," Joseph said.

Three of the adjustments are in the pack, with Wimpie van der Walt taking over from James Moore at lock, Yoshitaka Tokunaga coming in at openside flanker for Pieter "Lappies" Labuschagne, and Leitch, who was on the bench last week, replacing Kazuki Himeno at No. 6.

(Japan coach Jamie Joseph)

In the backs, Yutaka Nagare replaces Kaito Shigeno at scrumhalf, while Lomano Lava Lemeki takes over from Kenki Fukuoka on the left wing.

"We have a fair idea on who we think our best players are, but there are some positions where there is a lot of competition where we want to give everyone an opportunity," said Joseph, explaining the changes at lock, scrumhalf and wing.

"I thought Jimmie Moore last week played a very good first test match but the incumbent is Wimpie...Shigeno played well last weekend but we are giving Nagare an opportunity (because) he is a senior player in the team and a great leader, and creates a lot of confidence in our preparation week."

"Wings are very competitive with Mano (Lemeki), (Kotaro) Matsushima and Kenki as our three senior wingers, so we just want to give those guys an opportunity and see how the combination goes."

Injuries and rehabilitation have also influenced the movement of players in and out of the lineup, including the return of captain Leitch.

Last week's captain Labuschagne is still recovering from a medial ligament strain to his knee, while scrumhalf Fumiaki Tanaka (hamstring) was not risked as he is still less than 100 percent.

Leitch gets his first start since December 2018 as he continues to recover from a long-standing groin issue.

"We need him to get some game time," Joseph said of his skipper. "Himeno was unlucky not to stay in the team. He played very well last week but we really wanted to give Michael some game time."

Lock Uwe Helu gets a recall from an injury absence, joining Himeno, Shigeno and Fukuoka on an otherwise unchanged bench.

The two sides have played 17 times with Japan winning eight, including the most recent meeting, a 39-6 drubbing in Toulouse, France, in November 2017.

The PNC sees the six participating nations split into two pools with teams playing the three sides not in their group, with the ranking determined across the tournament schedule.

The Brave Blossoms' final game will be against the United States on Aug. 10 in Fiji.