Matthews controlled much of the race, keeping Spirig at bay throughout the bike and only losing the lead briefly on the run before taking it back soon after.
In Sub7, Blummenfelt emerged from the swim with a surprisingly substantial lead over Skipper, but the Brit hunted the Norwegian down on the bike and passed him with his trademark bark.
However, as expected by many, Blummenfelt came back strongly on the run, passing Skipper and taking the tape with a gap of a few minutes.
Kat Matthews and Nicola Spirig warm up ahead of the start of Sub8 (Credit: Mana Group/Pho3nix Foundation)
Matthews and Spirig share an embrace as they prepare to begin their Sub8 attempt (Credit: Mana Group/Pho3nix Foundation)
Blummenfelt watches as Joe Skipper edges away on the bike. Moments before, the Brit passed the Norwegian with a trademark bark (Credit: Mana Group/Pho3nix Foundation)
Matthews stays on the rear wheel of her pacing team and slowly increases her advantage over Nicola Spirig (Credit: Mana Group/Pho3nix Foundation)
Falling in behind his pacing team, Blummenfelt keeps the power down as he tries to maintain a consistent speed (Credit: Mana Group/Pho3nix Foundation)
Spirig falls in behind her pacing team on the bike leg of Sub8. She’s the only athlete competing on a road bike (Credit: Mana Group/Pho3nix Foundation)
Matthews keeps her eyes on the prize during the 180km bike leg (Credit: Mana Group/Pho3nix Foundation)
Spirig digs deep on the run to pass Matthews, but is later overtaken and fades to second (Credit: Mana Group/Pho3nix Foundation)
Skipper employs a novel technique to help him stay cool on the run (Credit: Mana Group/Pho3nix Foundation)
Paced by fellow triathlete Ruth Astle, Matthews maintains a steady pace on the marathon to take the win (Credit: Mana Group/Pho3nix Foundation)
Blummenfelt celebrates with the crowd as he runs down the finishing chute (Credit: Mana Group/Pho3nix Foundation)
Matthews celebrates as she takes the win over Nicola Spirig and successfully goes Sub8 (Credit: Mana Group/Pho3nix Foundation)
Nicola Spirig is all smiles after posting a time of 7:34:19 during Sub8, just a few minutes down on Kat Matthews (Credit: Mana Group/Pho3nix Foundation)
Joe Skipper and Kristian Blummenfelt share an embrace after both athletes finish the iron distance in under seven hours (Credit: Mana Group/Pho3nix Foundation)
Kristian Blummenfelt takes a moment to gather his thoughts after going Sub7 (Credit: Mana Group/Pho3nix Foundation)