The versatile Welsh international will reach the landmark at Parc y Scarlets on Saturday evening, a little over five years after making his regional debut as a second half replacement for Tom Smith in a 9-9 draw with Glasgow at the Liberty Stadium in 2009. His first start came a couple of weeks later in an LV= Cup defeat away to Bath, the same day that Justin Tipuric made his first start.
Since then King has established himself as an important member of the squad, the Australian born North Walian taking the Coaches' Player of the Year award last season. His consistency has been recognised by the national set-up, with three Wales caps to his credit to date.
Speaking ahead of his 100th cap, King said:
"It's a great landmark to reach and obviously I'm delighted about it. I've been with the Ospreys since coming down in 2008 and I've really grown up here in terms of my rugby development. It's been a great environment to learn my trade, working with quality players and coaches, I've been very privileged with the experiences I've had.
"When you're a youngster starting off you just want to play as much as you can, so to reach 100 games in the short time I have is something I really appreciate.
"I'm still a young man, I'm only 24, so I just want to be involved regularly, play my part for the team, and keep learning. If I can do all that I'll be happy."
Andrew Millward, Rugby General Manager, paid tribute to King on reaching the 100 mark.
"James was identified as a teenager with real potential and he has really thrived in our environment since he made the move from Mold as an 18-year old," said Millward.
"As the latest product of our development pathway to reach 100 caps, he is in good company. He's an outstanding professional, diligent and hard working, and a consistent performer wherever he has been selected to play, be it six, seven, or in the second row.
"That consistency demands selection, week in, week out, and he is probably enjoying his best season yet as an Osprey. To have reached 100 appearances at the age of 24 is an achievement to be proud of, particularly when you consider the strength in depth we have traditionally had in the back five positions.
"What's best about James is he is never satisfied with his performance, he is always striving for excellence, and it is that motivation that will hopefully ensure many more appearances in an Ospreys shirt over the coming seasons."
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