Hackett first achieved prominence on debut at the 1997 Pan Pacific Championships, where he first won the 1500 metres. He also won the 400 m freestyle, recording his only international victory over the yet-to-be-famous
Ian Thorpe at the distance in international long course competition.
1998 World Championships During the 1998 World Championships, he again won the 1500 m but was narrowly upset by Thorpe in the 400 m. He also combined with Thorpe,
Michael Klim and
Daniel Kowalski to win the 4 × 200 m freestyle relay, beginning a six-year winning streak in the event over the United States. These results were replicated at the
1998 Commonwealth Games in
Kuala Lumpur. From 1997 to 2007 he was unbeaten in the 1500 m, winning it at every major world competition, including the World Championships, Pan Pacific Championships, Olympics, Commonwealth and Australian Championships. In 1999, Hackett broke his first world record, unexpectedly breaking
Giorgio Lamberti's 200 m freestyle world record while leading off his club relay team at the Australian Championships. That record was subsequently broken by Ian Thorpe in the same year at the 1999 Pan Pacific Championships in Sydney, although Hackett himself bettered his old mark. Hackett himself claimed the 1500 m freestyle, and combined with Thorpe, Klim and
Bill Kirby to break the world record in the 4 × 200 m freestyle.
2000 Summer Olympics Entering the Sydney Olympics in 2000, Hackett was the overwhelming favourite in the 1500 m freestyle, and was also expected to help Thorpe take a
quinella in the 200 m and 400 m events. However, due to a virus, he was well short of his best and finished eighth and seventh, respectively, in these events. He followed this with an extremely slow swim in the heats of the 4 × 200 m freestyle relay, and was dropped from the final quartet, being replaced by
Todd Pearson. By the time the final of the 1500 m freestyle came, Hackett had qualified third behind sentimental favourite
Kieren Perkins, who was being vocally cheered by the crowd. In the face of the immense pressure, Hackett adopted a more attacking, fast-starting approach, and managed to hang on to claim gold.
2001 World Championships At the 2001 World Championships in
Fukuoka, Hackett was in the peak of his speed. He set personal bests in the 200 m, 400 m 800 m and 1500 m freestyle events, finishing second to Thorpe in both 400 m and 800m, and bettering the 800 m world record in the latter. Along with Thorpe, Klim and Kirby, they bettered the previous world record in the 4 × 200 m freestyle. In the 1500 m, Hackett attacked immediately, and stayed well ahead of Perkins' world record, and with the crowd standing and willing him on, he broke the record by 7 seconds, to claim gold.
2003 World Championships In the 2003 World Championships in Barcelona, Hackett picked up five medals; three gold, a silver and a bronze. Despite capturing individual medals in 200, 400, 800 and 1500 freestyle events for the first time in an international meet, Hackett failed to break any personal best times.
2004 Summer Olympics At 196 cm (six foot five) and 89.8 kg (198 pounds), Hackett won the gruelling 1500 metres race by sheer physical strength and stamina. He showed this in Sydney when he won despite having only partly recovered from illness, and again in Athens, when he survived challenges from swimmers (
Larsen Jensen and
David Davies) both six years his junior to hang on to win the race, despite a partially collapsed lung. This came after a solid swim in the 400 m to claim silver behind Thorpe, and a lackluster performance in the individual 200 m, followed by an unconvincing swim in the lead-off leg of the 4 × 200 m relay, when he was 1.66 seconds off his best. His sluggish heat swim placed him third, raising concerns within the Australian camp. After the Olympics, it was revealed that one of his lungs was partially collapsed, leaving his total lung capacity diminished by 25%.
2005 World Championships In 2005, Swimming Australia introduced the concept of a captain for the swimming team. Hackett was awarded this honour, and led Australia in the World Championships at
Montreal, Quebec, Canada. He won gold medals in the 400 m, 800 m and 1500 m freestyle (as well as silver in the 200 m freestyle), the first person to achieve this feat, along with the only swimmer to medal in four distances in a single world championships. His victory in the 800 m event broke Thorpe's world record, and his 1500 m victory saw him become the first to win an event four times at a World Championships. He anchored the 4 × 200 m team to bronze with a split of 1:44.84, making him the second fastest performer in relay splits. He was named as FINA's Male swimmer of the meet. In November 2005, Hackett announced his withdrawal from the
2006 Commonwealth Games due to being unavailable for the selection trials because of a minor surgery to correct a shoulder injury. However, he was given dispensation to act as a non-competing captain in order to mentor the fellow swimmers in the lead-up to the competition. In late 2006, Hackett relocated to Melbourne for personal reasons. He attributed his disrupted preparation to adjusting with his new regime. Prior to the
2007 World Aquatics Championships, he presented a pessimistic outlook of his prospects.
2007 World Championships He qualified last in the 400 m event, but led in the final before fading in the last lap to take the bronze medal. He qualified fifth in the 800 m event, but finished seventh, more than ten seconds behind the winner. In the 1500 m final Hackett came seventh, ending his decade long unbeaten streak in the event. In December 2007, Hackett competed in and won his first national championship 10 km Open Water race. By barely edging out veteran open-water swimmer and
surf Ironman Ky Hurst, the pair both qualified for the World Championships in Seville, Spain. However, Hackett failed to finish in the top 10 in this event, and therefore missed out on qualifying for the 10 km open water swim at the 2008 Summer Olympics. He was also criticised for appearing to be overweight after the event, a claim that he rejected as "ridiculous". At the 2008 Victorian Short Course Swimming Championships, his final Australian meet before departing for the Olympics, Hackett broke his own 800 metres freestyle world record – lowering the mark by almost two seconds to 7:23.42.
2008 Olympics Though Hackett failed to qualify for the 10,000m; he succeeded in other events. He swam the 400m and 1500m freestyle and the 4 × 200 m freestyle relay. In the 1500m he finished second, winning the silver medal behind
Tunisian
Oussama Mellouli. Had he won, he would have been the first male swimmer to win three successive Olympic titles in the same event, an opportunity denied to two-time Olympic 1500m champion
Vladimir Salnikov due to the
1984 Summer Olympics communist boycott. Hackett won the individual 200m freestyle swim at the Olympic trials but as he was not seeking a berth in the event he handed his spot in the Olympic competition in this event to the third-place finisher at the trials,
Nicholas Sprenger.
2015 World Championships Comeback After six and half years since racing a major competition and after six months of training under his belt. At the Australian Championships, Hackett finished fourth in the 200m freestyle, qualifying for the 4 × 200 m freestyle relay for the
2015 World Aquatics Championships. He also won a bronze medal in the 400m freestyle. At the 2015 World Championships in Kazan, he won a bronze medal for swimming in the heats of the
4 × 200 m freestyle relay, thereby winning his first international medal since the 2008 Olympics. ==Career best times==