The 22-year-old, who quit his banking job in Auckland last September to train full-time in a bid to qualify for August's Rio de Janeiro Olympics, won the 200m and 400m races.
It was a promising start to the busy part of the season for the Hill City-University sprinter, who clocked 21.94sec and 47.08sec in the 200m and 400m respectively.
Whyte's favoured event is the 400m, and his Otago record and personal best (46.42sec) is the sixth-fastest time in New Zealand history.
He was 3.20sec faster than second-placed Robert Jopp, of Hill City-University, in the 400m on Saturday, and edged club-mate Terry Collins-Hawkins by 0.67sec to win the 200m.
They were the most competitive fields Whyte had faced since his first race of the season a couple of months ago.
With a lack of competition at the weekly Caledonian Ground meets, Whyte is eyeing up whether it will be worth competing at the Capital Classic in Wellington later this month.
However, he said it appeared there would not be enough competition there and would instead look at heading to Australia.
He hopes to record a B qualifier (45.80sec) in his quest to get to Rio before or at the national track and field championships in Dunedin in March, but will head to Europe if he does not.
Otago's Hanna English also impressed on Saturday. The Ariki athlete won the women's open 3000m and finished third in the open mile.
She crossed the line in 10min 50.12sec in the 3000m, well clear of Timaru's Martina Fellmann, who finished in 11min 10.33sec.
English's time of 5min 17.96sec over a mile was also a personal best.
Other highlights in Timaru:
● Felix McDonald, of Taieri, won the men's open 400m hurdles in 59.21sec and finished second in the under-20 110m hurdles (15.34sec) and open men's long jump (6.69m).
● Christina Ashton, of Taieri, finished second behind Canterbury's Fiona Morrison in the women's open 200m (26sec) and was third in the 100m (12.56sec) and third-equal in the 100m hurdles (14.57sec).
● Terry Collins-Hawkins, of Hill City-University, finished second in the men's open 100m in 11.11sec.
● Michael Scholten, of Taieri, was second in the men's open hammer throw (39.39m).
● Danica Davies, of Taieri, finished second in the women's under-20 100m hurdles (15.98sec). She was pipped by 0.01sec by Christchurch's Rebecca Gillett.
● Adriana Mawhinney, of Alexandra, finished second in the open women's high jump (1.60m).
● Sam Gouverneur, of Taieri, finished third in the open men's 800m in 2min 2.21sec.
● Caden Shields, of Hill City-University, finished third in the men's open 3000m in 8min 39.22sec.
