Mount Maunganui surfer Kehu Butler will have piqued the interest of seasoned surfers after blazing his way to the highest heat score in the Open Division at this year's 2015 Billabong National Surfing Championships.

With the likes of Kiwi superstars Daniel Kereopa and Maz Quinn in the mix, the occasion didn't seem to trouble the Mount teen, who posted a 17-point total on the opening day at Piha.

Mount Maunganui's Kehu Butler. Photo: File.

The next best was Kereopa with 13.83 and the Mount's Mac Christie's 13.23.

Butler, 14, earlier won his heat in the Under-18 Boys Division and will enter the water today in the Under-16 Boys Division, ensuring a busy week of surfing.

In what is the 11th time the event has been held at Piha, a mix of competitors old and new advanced in the 1m waves on offer at the south end of Piha Beach.

And a return to the competitive arena for Kereopa saw him comfortably win through to the second round where the top seeds of the event will enter the water.

Kereopa last contested the National Championships in 2009 when the event was held at the same beach, placing second to Matt Hewitt of Mount Maunganui.

Six years later Kereopa is on course to meet Hewitt in the next few rounds should he progress, but in the meantime he is confronted with top seeds Maz Quinn (Gis) and Elliot Paerata-Reid (Piha) in the next round of the event.

As part of the old guard, Kereopa was joined by local surfer Liam Joyce as well as Marc Moore (Auckland) and Richard Dowsett (Whangarei), who claimed heat wins for the older generation of the competitors in round one of the Open Men's Division.

Other surfers to win their first round match ups in the Open Men's Division included Sean Peggs (Tairua) and William Cooper (Mount).

Flying the youthful flag along with Butler is Coby Perkovich (Taranaki), who secured a strong heat win in his first National Championships.

The 21-year-old, who is based in Australia, completed several big forehand turns on his two scoring rides to post an 11.5 point heat total and progress alongside Manu Soctt-Arrieta (Sandy Bay).

Late in the day the Under-16 and Under-14 Boys Divisions were contested with the youngest surfers in the event getting to hit the big stage at Piha.

In the Under-14s, many of the groms were competing for their first time at the event. While they loved the experience and got to surf against the best surfers from around the country, it was the top seeds that dominated proceedings.

Gold Coast based Kiwi Kaya Horne had a blast in both disciplines, winning his heats with 16 and 13-point heat totals.

Horne was joined by Reuben Fleetwood (Whangamata), James Ririnui (Mount) and Caleb Cutmore, who all won their Under-16 heats.

In the Under-14s, Horne was joined by Lucca Lind (Taranaki), Dylan Preston (Whangamata) and James Ririnui (Mount), who all won their respective heats to move through to the semi-finals.

The swell is forecast to build throughout day two of the event with light winds predicted. The 2015 Billabong National Surfing Championships runs until January 17.