Japan's two-test series against Ireland was always going to be about celebrating the achievements of a veteran lock. But the player being lauded is not the one most expected as injury means Hitoshi Ono is still stranded on 98 caps leaving another veteran to step into the limelight.

Luke Thompson retired from international rugby after the 2015 Rugby World Cup, having won 63 caps for Japan.

But with the Brave Blossoms in the midst of an injury crisis, the 36-year-old once again returns to international duty.

"We've got five locks out with injury so it was an SOS call," Japan head coach Jamie Joseph said of his chat with Thompson after last week's 50-22 defeat to the Irish.

"We need a player of his caliber and confidence, of his physical presence and experience. His presence creates confidence and you can build confidence around him."

So instead of lining up for Kintestu Liners against Kobe Kobelco Steelers in a preseason game, Thompson -- who spent a couple of seasons in Ireland playing for the Blackrock club before he headed to Japan in 2004 to initially play for Sanyo (now Panasonic) Wild Knights -- will be donning the shirt that means so much to him.

"I got the call on Saturday night and had to check with a couple of people first. I had already spoken to Kin-chan (Ono) so I knew he was out."

"Japan have given me a lot of opportunities and it is a real honor to wear the jersey. At the same time I don't want to disrespect it. I don't want to turn up and play like a mug. I want to do it justice."

Fortunately, as he pointed out, it is not as if he had retired completely from the game, as he still has another year left on his contract with Top League side Kintetsu.

"It's not like I have been brought in off the street. I am fit, very fresh and injury free and just want to do my job."

A job he is very good at, according to Japan captain Michael Leitch.

"You can put your house on Tommo. He always gives 110 percent."

A point expanded upon by Joseph.

"He's been very good. He picked up all the new calls on the first day and that's what you get when you pick an experienced football player."

Having played in three World Cups in sides led by John Kirwan and Eddie Jones, Thompson said he was excited by the challenge.

"There is a different vibe. There are a lot of new kids and I now know how Kin-chan feels as I am the oldest by four or five years. It's been enjoyable and refreshing. The new style and moves, it's been a good learning."

Thompson is adamant this is very much a one-off appearance in a time of need.

But as he headed for an ice bath to recover from a training session that by his own admission he thought he would never experience again, he did turn back and add with a smile "Never say never."