The Chris Tudor Memorial 50km race followed a course from Vauxhall Yacht club to Taiaroa Heads, where riders did a U-turn and headed back to Portobello.
From there, they went left and headed up Highcliff Rd to the finish on Shiel Hill.
The cyclists set off in six bunches, with the lead bunch having a 26min head start on the scratch bunch, which included Trotman.
Riders enjoyed a tail wind on the outward leg and the scratch bunch averaged 50kmh-55kmh.
The bunches remained largely intact until after the turn when the pressure was applied by those eager to get a head start on the looming climb ahead.
The scratch bunch caught up with the break on the return leg to Portobello and the amalgamated group began the climb together, but were quickly dispersed as the hill climbers found their unrelenting rhythm.
Lachie McGregor, Jeff Williamson and Chris Harvey from the break, along with Trotman and Stu Crooks from scratch, were dominant on the steep incline as they worked their way through the field.
But it was Justin Evans from the middle bunch who got home first, with Jan Brosnahan hot on his wheel for second overall and first woman. Williamson and McGregor battled it out for third all the way to the line, with Williamson narrowly edging out the teenager in a two-man sprint finish.
The lightweight Trotman had lost ground on the descent but powered to the line for ninth place in the fastest time of the day of 1hr 18min.
Trotman, who has completed her study at the University of Otago, will now head to Christchurch to concentrate on her build-up for the elite road national championships in January before joining the New Zealand squad based in Germany for 2013.
She credited Otago's hills for inspiring her love of cycling and thanked the members of the club for the support and encouragement she had received in her meteoric rise in the sport.
The junior race finished 200m up Highcliff Rd and was won by Columba College pupil Phoebe Swale.
The winners of both races were awarded the Chris Tudor trophies donated by the family of the promising young rider who was killed in a collision with a truck while out on a training ride 19 years ago.
- Janice McClelland
