HOBART (AFP) - First-time Sydney to Hobart winner Investec Loyal celebrated in earnest Thursday after an international racing jury upheld its nailbiting line honours victory over favourite Wild Oats XI.

The 100-foot supermaxi was formally crowned winner of the 628-nautical mile bluewater classic after a five-nation jury dismissed a race committee protest that it had received outside assistance.

"It's very relieving to actually get to this point," said visibly emotional Loyal skipper Anthony Bell after the ruling. "There's rules in every sport and I suppose, while it wasn't ideal to have to go through this, I think that ultimately it gets (the result) beyond any question."

The protest, centred on claims that Loyal had gained an unfair advantage by asking a media helicopter crew what sail five-time winner and current race record holder Wild Oats XI was flying, overshadowed the thrilling race finish.

Loyal had never been far from Wild Oats' tail, and it crossed the line just three minutes and eight seconds ahead after gaining on the veteran race favourite during the final stretch to Hobart.

 It was the fourth-fastest result in the race's 67-year history, and a sweet victory for Bell, who was runner-up in 2010 and long a rival of Wild Oats.