He was a promising youngster and represented New Zealand at the world youth championships in Italy in 2009. He was in the 4x100m relay team that came fourth.
Johnston demonstrated his class when he convincingly won the men's 100m at the Caledonian Ground on Saturday.
He sped down a rain-soaked track on the opening day of the Otago athletics season in 11.28sec. He was followed home by George Woodhouse (Hill City-University), 11.82sec, and Mackenzie Haugh (Taieri), 11.86sec.
''I have been out of action for three years and it is great to be back,'' Johnston said.
Johnston (21), a marketing student at the University of Otago, has trained hard in the winter months with Brent Ward's sprint squad.
''We have worked on Todd's start and he is now staying lower when he comes out of the blocks,'' Ward said.
''We also worked on his running stride to get more relaxation.''
Johnston had success at national level in the past and won two silver medals in the 100m in 2008, at the New Zealand secondary schools championships and, four months later, in the under-16 club championships.
He still holds the Otago aged 13 records for the 100m (11.94sec) and 200m (24sec). His personal-best times are now 10.85sec for the 100m and 22.33sec for the 200m.
The big guns fronted up in the men's 200m, won by Daniel O'Shea (Hill City-University) in 22.01sec from clubmate Andrew Whyte, 22.02sec.
O'Shea is a contender for the Glasgow Commonwealth Games in the 400m hurdles and Whyte in the 400m flat.
But they were outgunned in the 200m by visiting South Canterbury sprinter Jacob Matson (16), who won the men's aged 15 to 17 race in 21.92sec.
Chris McNoe (Hill City-University), another member of Ward's squad, pulled away in the front straight to win the men's 400m in 52.10sec. Clubmate Tim Morrison was second in 53.96sec.
McNoe (17) was in the Otago Boys' High School First XV this year and the hard winter training has kept him fit for the athletics season.
He was close to his personal-best time of 51.80sec and this will give him confidence as he prepares for the New Zealand secondary schools championships in Hamilton in December.
Christina Ashton (Taieri), the winner of the junior girls hurdles last year, is chasing the senior girls title at the same championships.
She gave notice that she will be a contender by winning the 100m hurdles in 15.54sec on Saturday.
Ashton (16) was second in the flat 100m in 13.14sec. The race was won by Caitlyn George (Hill City-University) in 13.09sec and she also won the 200m in 26.74sec to take the women's sprint double.
Sam Bremer (Hill City-University), who is also peaking for the secondary schools championships, sprinted the last lap in 64 seconds to win the men's 1500m in 4min 05.74sec.
Alexandra jumper Adriana Mawhiney (15) won the women's aged 15 to 17 long jump (4.77m) and the triple jump (10.55m).
