Education
Gregson finished 5th in the boys" 1500 metres at the 2007 World Youth Championships in Ostrava. At the 2008 World Junior Championships in Bydgoszcz he again finished 5th over 1500 metres and also participated in the 5000 metres. Gregson finished 4th in the 1500 metres at the 2009 Summer Universiade in Belgrade, Serbia, missing out on medaling by only 0.22 seconds.
Career
He holds the Australian record for the men"s 1500 metres, both outdoors and indoors. Youth
Later that year, he set new Australian youth records over 1500 metres, 3000 metres and 5000 metres, his 3000m clocking of 8:01.26 also eclipsing Craig Mottram"s Australian junior record. In 2009, his last year as a junior, he set new Australian junior records over both 3000 and 1500 metres, with times of 7:57.45 and 3:37.24 respectively.
2009-present
Gregson also qualified for the 2009 World Championships in Berlin, Germany, where he again competed in the 1500 metres and was eliminated in the heats.
Gregson next appeared in a Diamond League race on 24 July, in the Herculis meet at Fontvieille, Monaco. He was eliminated during the semi-finals of the Olympic 1500m in London at the 2012 Olympic Games.
JULY 2012
5/7/12 1500m Sollentuna Grand Prix Stockholm, Sweden 6th, 3:39.89
17/7/12 Mile 61st Cork City Sports Cork, Ireland 1st, 3:57.98
25/7/12 Mile Morton Pre Games Dublin, Ireland 3rd, 3:56.45
JUNE 2012
7/6/12 Dream Mile Oslo Diamond League Oslo, Norway 10th 3:53.62
14/6/12 800m Folksam Grand Prix Gothenburg, Sweden 9th 1:49.06
MAY 2012
11/5/12 1500m Doha Diamond League Doha,Qatar 11th 3:33.92
24/5/12 800m Hyundai Grand Prix Oslo, Norway 2nd 1:48.29
27/5/12 1500m Meeting International Mohammed V1 d"Athletisme Rabat, Morocco 19th 3:48.39
APRIL 2012
1/4/12 5 km Road Carlsbad 5000 California, United States of America 7th 13:39 PB
28/4/12 Direct Market Reseller Penn Relays Philadelphia,United States of America 5th 9:24.76
MARCH 20122/3/12 1500m Olympic Trials Melbourne, Vic 1st 3:38.51
FEBRUARY 2012
4/2/12 800m Briggs Athletics Classic Hobart, Tas 3rd 1:49.82
JANUARY 2012
28/1/12 1500m Adelaide Track Classic Adelaide, Société Anonyme 1st 3:47.84
SEPTEMBER 20111/9/11 1500m San Francisco World Championships Daegu, South of Korea 8th 3:47.89
10/9/11 1500m Rieti 2011 Rieti, Italy 12th 3:47.05
AUGUST 2011
JULY 2011
22/7/11 1500m Monaco Diamond League Monte Carlo. Monaco 14th 3:51.05
20/7/11 1500m Stockholm Diamond League Stockholm, Sweden 11th 3:39.08
JUNE 2011
4/6/11 International Mile Prefontaine Classic Eugene, United States of America 1st 3:53.86
12/6/11 3000m Meeting De Strasbourg Et Des deoxyribonucleic acid
Strasbourg, France 9th 7:49.53 PB
28/6/11 1500m Sollentuna Grand Prix Stockholm, Sweden 2nd 3:36.64
APRIL 2011
30/4/11 Direct Market Reseller Penn Relays Philadelphia, United States of America 2nd 9:17.56 NR.