Marco Gradoni is evidently not a sailor who pays much attention to old superstitions. The 22-year-old tore through a practice day that was supposed to be low-stakes, producing a performance so commanding it immediately set the competitive benchmark for everyone else in the Louis Vuitton 38th America's Cup Prelim Regatta fleet.

The Luna Rossa Women & Youth team were the story the fleet could not ignore. Gradoni was joined by Women's America's Cup winners Margherita Porro on co-helm and Maria Giubilei on trim, alongside newcomer Giovanni Santi also on trim. Together they generated speed that nothing in the fleet could match across the day's three races, aided by near-perfect conditions: 12 knots of breeze and a mild sea state that allowed the foiling machines to perform at their best.

Luna Rossa 1 had the opening race under control almost from the gun. Their lead grew steadily and looked all but unbreakable until, approaching the first leeward mark, a slow board raise on the starboard side pitched the bow down and cost them precious moments. La Roche-Posay Racing Team was closing fast behind.

What this young Italian crew did next revealed more than pace alone ever could. Gradoni bore away, rebuilt speed, climbed back onto the foils and drove clear. The gap had been cut, but the outcome was never seriously in doubt. By the finish, Luna Rossa 1 had stretched their advantage back out to 26 seconds over La Roche-Posay Racing Team, a notable margin in one-design foiling racing. Emirates Team New Zealand's senior squad crossed in third.

The second race produced a lively beginning, with the whole fleet executing their time-on-distance runs sharply and reaching around 32 knots of boatspeed at the starting line. Two groups formed across the course. Luna Rossa 1 picked up a penalty early and had to sail up the middle after clearing it with a 75-metre getback. As the fleet compressed through the first windward leg, Gradoni and Porro made a decisive call, peeling out to the far boundary to find clear air away from the congestion. They came in with room to breathe and stunned the fleet, arriving at the first gate ahead of everyone, including the senior Luna Rossa boat sailed by three-time Cup winner Peter Burling.

For the next four legs, the two Luna Rossa entries appeared to be conducting a private match race of their own, well clear of the rest. The separation came on the second upwind. Burling and Ruggi Tita caught a favourable shift out to the left while Gradoni and Porro worked the right side of the course and struggled to match it. Then came the moment that decided the race. Gradoni crossed Tita on starboard tack and called for a slam-dunk, tacking directly on the wind of the senior team. It was an aggressive move, and it ultimately decided the race. Team Director and CEO Max Sirena, watching on, faced the high-class problem of seeing two of his own crews produce racing of that calibre.

Luna Rossa 1 powered clear to take their second win of the day by some 20 seconds. Burling, meanwhile, was caught out on the final approach to the finish line and lost a place to GB1, with Dylan Fletcher and Ben Cornish sailing a fine final leg to slip in at the far end of the line.

Race three opened with more tactical complexity at the start. Luna Rossa 1 Women & Youth hung out to the far left of the starting line with seconds to go before tacking back on port, with Margherita Porro seeking clear air out on the right boundary. Nathan Outteridge and Seb Menzies in Emirates Team New Zealand followed a similar path. The start, however, belonged to GB1. Dylan Fletcher absolutely aced the start and headed to the left boundary, building a lead the British team would never relinquish. Burling and Tita's race unravelled when they collected a boundary penalty and were subsequently disqualified for failing to take it in time, turning what had been a fleet contest into a two-horse affair very quickly.

Over six legs, GB1 and Luna Rossa 1 traded blows while pulling steadily clear of the pack. The British team's front-running composure was exceptional. They kept their tactics conservative, covered every move Gradoni and Porro made, and no amount of Italian pace could match it. GB1 crossed the line 18 seconds clear.

Practice racing it may have been, but the day's three races offered a revealing picture of the competitive order. Marco Gradoni and Margherita Porro sit at the top of it. Luna Rossa 2 with Peter Burling and Ruggi Tita carries genuine speed, and GB1 look right in the fight. The first Preliminary Regatta begins in earnest tomorrow, with three races scheduled from 15.13 local time.

Sardinia is stunning and the racing is electric. The fight for the Louis Vuitton 38th America's Cup Prelim Regatta, Sardinia, is on.