Jackson "Jacko" Gill (born 20 December 1994) is a shot putter from New Zealand.
At the 2010 World Junior Championships in Athletics, he won a gold medal in the shot put. He is the youngest-ever male junior champion (age 15), beating the previous youngest, Usain Bolt, 2008 Olympic sprint champion and world-record holder. Gill won the gold in the shot put (6 kg) with a distance of 20.76 m, beating 18- and 19-year-olds.
In 2010, prior to the World Junior Championships, Gill threw the 5 kg shot 22.53 m at an event in Stockholm, Sweden, exceeding the best-known performances with that weight for 15- and 16-year-olds. He improved to 22.60 m in finishing second at the inaugural Youth Olympic Games despite being unwell.
On 11 December 2010, at the New Zealand National Secondary Schools Championships, Gill set a youth (under-18) world-best performance of 23.86 m (5 kg).
On 26 March 2011, at the New Zealand National Championships, Gill achieved 21.34 m with the 6 kg shot, at the time ranking him 4th on the all-time IAAF junior list for shot put.
On 23 April 2011, at 16 years of age, Gill threw 20.01 m with the senior shot (7.26 kg). This performance surpassed the standard for the 2011 Athletics World Championships, however the rules for that competition exclude anyone of Jacko's age competing in any throwing events. An appeal to the IAAF for an exception to be made to this regulation to allow Gill to compete was rejected.
On 7 July 2011 at the 2011 World Youth Championships in Athletics in Lille Métropole, France, Gill won the gold medal by 4 m with a World Youth Best Performance of 24.35 m with the 5 kg shot.
He went on to qualify for the 2012 Olympics on 5 December 2011 by throwing 20.38m with the 7.26 kg shot. On the same occasion he threw 22.31 with the 6 kg shot to move become the second furthest junior (under-20) thrower ever with that weight. Gill has been reported as the youngest and one of the lightest athletes to throw over 20 m.
Gill's father, Walter, is a former discus thrower and national shot-put champion, and his mother, Nerida, is a former discus thrower.