They adjusted the blades. They took silver medals behind Norway at Munich last month. Normal propulsion had been resumed.
The relieved smile on 25-year-old Joseph Sullivan's face said it all as he relaxed earlier this week at the bed-and-breakfast establishment the team is using during the day between training and races in Buckinghamshire, near the Dorney Lake course.
"Something had gone wrong in transit from New Zealand. The bottom part of the blade's curve - which we don't tend to measure - was at the wrong angle on both oars on the right-hand side. It was good news because that was a stressful time. We were getting angry at each other and blaming each other but it was actually the fault of the equipment," Sullivan laughs.
"It was a big relief. We only found out two days before Munich and it was only by chance. ... We're feeling a lot better now; we've got more confidence and feel amped."
The discovery pushes Cohen and Sullivan back into strong medal contention with the likes of the Norwegians and the Germans. The Australian crew of Scott Brennan and David Crawshay probably remain favourites. The defending Olympic champions had two years off after Beijing, came fourth last year and took silver at the 2012 World Cup in Lucerne.
However, a fully functioning boat means Sullivan and Cohen should be right near the apex of the field, particularly as they have proven composure to win close races. Last year's world championship final was an example. They pipped Germany by 0.06s. The first time they hit the front was on the line.
New Zealand had never been the best in the world at the men's double sculls before these two came together. Cohen's previous partners had included Matthew Trott (2007, 2009) and Rob Waddell (2008).
Lucerne this year is also not the first time this combination has suffered the heebie-jeebies followed by success. When they missed the final at the 2010 World Cup regatta in Munich, their world championship aspirations looked shot. They swapped boat positions for the next World Cup three weeks later in Lucerne. That produced a bronze which was followed by their world championship triumph on Lake Karapiro.
Deja vu anyone?