The Prince and Princess of Wales made a surprise courtside appearance on Wednesday to watch the Boston Celtics take on Miami Heat.
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William and Kate were cheered by spectators as they took their seats courtside alongside Massachusetts Governor-Elect Maura Healey, Celtics Legend Thomas "Satch" Sanders, and the team's two principal owners and their wives. The royal couple were welcomed to the arena by Wycliffe "Wyc" Grousbeck, Lead Owner of the Boston Celtics.
WATCH: Prince William and Princess Kate surprise crowds at Boston NBA game
Princess Kate was beaming from ear to ear as she took her seat next to Prince William.
The mom-of-three opted for a chic ensemble featuring a vintage blue tweed jacket by Chanel paired with black dress pants, while Prince William cut a dapper figure in a dark suit and chambray shirt.
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Kate accessorized her look with a gold link necklace and matching earrings, and wore her brinette hair in loose waves.
Before the game began, they were greeted by Celtcis player Jayson Tatum, and during the game, they appeared on the FanCam to loud cheers from the arena.
They sat courtside
The royal couple travelled to Boston on Wednesday for the second annual Earthshot Prize Awards Ceremony.
The glittering event has been described as William's "Superbowl moment" and is expected to draw an A-list crowd at the MGM Music Hall at Fenway in Boston, Massachusetts on 2 December.
Photographers caught Jayson greeting the Princess
Songstress Billie Eilish is poised to take to the stage as she heads a stellar line-up of talent which includes Annie Lennox, Ellie Goulding and the Beyoncé-backed R&B duo Chloe x Halle.
Earthshot Prize council members Sir David Attenborough and Cate Blanchett will both provide voiceovers during the ceremony, which will be presented by UK broadcaster Clara Amfo and US actor Daniel Dae Kim.
\Kate wore a vintage tweet Chanel blazer
Launched by the Duke and The Royal Foundation in October 2020, The Earthshot Prize has been inspired by President John F. Kennedy's 'Moonshot' programme in the 1960s, which urged millions of people to support the US space programme.
It is based on five 'Earthshot' goals: Protect and restore nature; Fix our climate; Clean our air; Revive our oceans; Build a waste-free world. Five £1 million prizes will be awarded each year for the next ten years, providing at least 50 solutions to the world's greatest environmental problems by 2030.
The two are in Boston for three days
Last year, the royal appeared in a poignant five-part docuseries centred on the planet's greatest environmental challenges and how we can fix them. During the first episode, William pleaded: "This is a moment for hope, not fear. A better sustainable future is within reach, we just have to grasp for it. We humans can achieve anything we set our minds to. So let's all set our minds to this, a decade of action to repair our planet. There's no time to waste."
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They lit up City Hall green
The Prince and Princess lit Boston up in green on Wednesday as they arrived in the city to rain.
William and Kate pressed a button to light up the rainy evening after joining Mayor of Boston Michelle Wu and Massachusetts Governor-Elect Maura Healey at Speaker’s Corner outside Boston City Hall, which was one of 16 landmarks transformed by lights to kick off the celebration.
Addressing the crowd gathered outside, the Prince thanked "all the hardy Bostonians braving the rain this evening".