Drysdale only got his nose in front inside the last 250m, winning in 6min 37.810s, with Martin one and a half seconds back, and Britain's Alan Campbell third.
The tall New Zealander has beaten two of his toughest rivals, Czech Republic oarsman Ondrej Synek and now Martin in the last two cup regattas in what might prove a significant psychological booster.
The lightweight four followed their win in Lucerene at the end of last month with another fine demonstration.
James Lassche, Matt Dunham - in for the injured Peter Taylor - Alistair Bond and James Hunter were in front at halfway and won in 5:48.340, almost 3s up on Denmark.
Manson and Harris had a terrific duel with the British double before winning by just .630s.
"It was good to come in first place. We have not had our best racing these last few days. There is still a lot to work on," Manson said.
For Murray and Bond it was business as usual.
''We are going well, we are in good shape and we know how fast we can go," Bond said last night.
The women's eight were in a three-boat race but impressed in seeing off Britain and the Netherlands, winning in 6:06.270, almost 2s ahead of Britain.
Women's pair Rebecca Scown and Genevieve Behrent had a quality duel with Britain's Olympic champions Heather Stanning and Helen Glover in winning silver.
Scown and Behrent finished one and a half seconds back but will be encouraged by the performance. Olivia Loe and Holly Greenslade, the second New Zealand combination finished sixth.
Silver medals also went the way of the women's double Eve Macfarlane and Zoe Stevenson, and single sculler Emma Twigg.
Macfarlane and Stevenson, world champions last year, have had a tough time of it, were sixth in the previous cup regatta in Lucerne and sixth in their heat in Poznan. But they found their form after a sluggish start in the final to roar through the field in the middle stages.
Twigg was well beaten by rival Kim Brennan of Australia, who blitzed the field. Brennan, two-time world champion, clocked 7:15.980, more than 3s ahead of 2014 world champ Twigg.
There was a bronze for the lightweight women's double of Sophie Mackenzie and Julia Edward in a keenly-contested race, crossing behind the Netherlands and Denmark. The Dutch pair of Ilse Paulis and Maaike Head set a world best time of 6:47.690 while the New Zealanders clocked 6:50.650.
That is shaping as a cracking battle for the dais in Rio.
The men's eight rounded off a stellar day with bronze, albeit some way behind powerhouses Germany and Britain.
