The 20-year-old Australian forward, who stood out at the 2026 World Cup, arrives at Alvalade from Watford, with Sporting paying 15 million euros for his transfer, plus another three million in add-ons, according to reports.
Irankunda signs until 2031 and is protected by an 80 million euro release clause.
Irankunda scored one goal in four matches for Australia at the 2026 World Cup. Last season, the 20-year-old winger played 42 games for Watford in the Championship, scoring four goals and providing four assists.
In his first words at his presentation, inspired by his celebration in tribute to Michael Jackson, Nestory Irankunda said he was "very happy and grateful to be" at Sporting.
"I accepted the offer thanks to conversations I had with people within the club's structure. The project seemed very good to me and, obviously, Sporting CP is a top club with a great history. I wanted to accept this challenge, and I'm ready," he told the club's media, continuing:
"Even someone who lives on the other side of the world, like me, looks at Sporting CP and understands how fantastic and passionate the fans are. That's why, and also because of the club's history, I get goosebumps thinking that I'm wanted by a club like this. When they told me about Sporting CP, it was Sporting CP all the way," he added.
Regarding his aims, Nestory Irankunda was clear: "I came to win titles and to play for great fans. I want to make history, and there is no better place to do that than at Sporting. I am very happy to be here, and I hope to win trophies this season."
Asked to describe himself, the new lion said he is "powerful, very fast and capable of jumping very high". "I can also score and create scoring opportunities for the team," added the footballer who has no problem playing "anywhere in the attack."
Intending to "stay a long time" at Sporting, especially because "words can't explain how happy" he is, Nestory Irankunda also commented on the possibility of making his debut in the Champions League.
"It's a moment of great happiness and pride. I'm very excited. Any child or person who loves football dreams of playing in the Champions League. Having that opportunity will be fantastic, and a dream come true," he emphasised.
In addition to his move to Sporting and the possible Champions League debut, Irankunda recently had a great experience at the World Cup.
"2026 was, so far, the best year of my career and I want to make it even better by having a great start at Sporting," he said.
About Michael Jackson, the theme of his presentation video and also his goal celebrations, the young forward explained the connection: "For me, he is the greatest artist of all time and a huge inspiration. I grew up listening to his music and watching him dance is fascinating. One day, before a game, I decided to do (the celebration), and I think I'll keep doing it because everyone likes it."
Finally, Nestory Irankunda addressed Sporting fans. "I'm ready to get started. We have a great season ahead, and we're going to win a lot," he promised.
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