The 19-year-old Taieri athlete has been rattling off personal-bests and has sky-rocketed to second on the national open men's long jump rankings.
That came thanks to a jump of 7.41m at the Rhythm and Jumps meet in Christchurch last month.
Just 2cm off the best jump in the country in 2017, it was a 17cm personal-best. Only 27 New Zealanders have jumped further.
McDonald carried that form on to the track at the South Island championships in Timaru on Saturday.
There he notched personal-bests in the 100m and 200m of 11.11sec and 22.40sec respectively.
It made for an impressive start to the season for the under-20 national and Oceania decathlon champion.
While the decathlon was still his overall aim, the long jump remained his top event at present.
''I think we're just working on speed and stuff and keeping with the long jump and slowly chipping away with the decathlon and getting all my other events better,'' he said.
''But at the moment long jump is pretty high up there, what I want to be doing at the moment, but I'm just giving all the other events a go and see what happens.
''I'm more going towards that sprinter, long jumper, hurdler kind of thing, that can also do other events.
''But slowly, I think, those other events will become stronger and will be even, but at the moment the long jump is definitely the strongest.''
Having come off a foot injury heading into last season, McDonald believed it had made a big difference having a winter of training this time around.
That had enabled him to establish a strong base to work from and he had done a lot of gym work to build power.
However, the foot was still causing some issues. He had modified his hurdles training and was making sure to not overload himself in the long jump.
Therefore he did not jump every weekend, although would do so at big competitions.
He found he jumped better when he was fresh and plyometric-type events such as the long jump could wear him down. The sprints did not cause the same impact, so he was doing one of those, plus a throw, most weekends.
McDonald, who will move into the senior grade in the new year, is targeting the Porritt Classic, combined events national championships and national championships later in the season.
