Dublin - Ireland lock James Ryan has signed a three-year contract extension, the Irish Rugby Football Union announced on Wednesday.
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The Leinster second row made his Test debut as a 20-year-old in 2017, scoring a try within 60 seconds of coming off the bench against the United States in New Jersey.
Ryan, 23, has become a regular in the Irish pack, winning 24 caps, and has won the European Champions Cup and two Pro14 titles with the Dublin-based province.
The deal ties Ryan, seen as a potential Test captain, to Irish rugby until the end of the 2022/23 season.
"A lot has been packed into the start of my professional career with both Ireland and Leinster and there has been some great success and a few disappointments," said Ryan.
"But I am involved in two very exciting squads that want to be challenging for trophies."
IRFU high performance director David Nucifora said: "James is still a young man but he has delivered consistent high-level performances for both Ireland and Leinster.
"He is growing into a leadership role with the national team and has a big future for both Ireland and Leinster."