As a two year old Christian Cullen won all of his five starts and $152,465. He won the Welcome Stakes and Sales Series Pace but his season was shortened by injury. In the 1997–98 season Christian Cullen won 5 of 10 starts with 2 seconds and 1 third and he earned $302,460. In November he won the New Zealand Sires Stakes 3yo Final and then beat older pacers in the $100,000 Round Up 1950 in a 1.58.1 mile rate over 1950 metres with a final 800 metres in 55.9 seconds. Christian Cullen then received an invitation to the Miracle Mile Pace in Sydney but was a late scratching due to a pre-race testing irregularity, however the control fluid was later found to be contaminated. Back in New Zealand he was an unlucky third to Holmes D G in the Great Northern Derby and won the Sales Series Pace but suffered an injury before the New Zealand Derby.
1998–99 season
Having recovered from injury Christian Cullen won several races early in the season including the Ashburton Flying Stakes where he beat Iraklis and became favourite for the New Zealand Trotting Cup. He was unofficially timed to have run the final mile of the race in 1:53.5. Christian Cullen then won the New Zealand Cup beating Iraklis with seven lengths to the third placed horse. The time of 4:00.4 equalled the race record. Three days later he won the New Zealand Free For All defeating Holmes D G running his last 800 metres in 54.4 seconds. Invited back to Sydney for the Miracle Mile Pace Christian Cullen won by 20 metres over Tailamade Lombo and Our Sir Vancelot in a mile rate of 1:54.4 for 1760 metres. He then displayed courage to win the Treuer Memorial at Bankstown in track record time. In the Auckland Pacing Cup Christian Cullen cruised home in 3:59.7 for 3200 metres but missed the Victoria Cup in Melbourne after suffering pneumonia. Christian Cullen then won two races at Cambridge Raceway including the Waikato Flying Mile where he won easily in 1:54.2 but did not attempt to break the national mile record due to the closeness of the upcoming Inter Dominion. He won an opening night heat of the Inter Dominion, for which he was even money favourite before the series had even begun, but suffered a leg injury which ended his season.
1999–00 season
Christian Cullen returned to the track as a five year in the Hannon Memorial but was unplaced. He then suffered from corns which kept him out of racing for several months. He won in 1:55.9 over a mile at Moonee Valley and was eighth in the A G Hunter Cup after being severely checked at the start. Christian Cullen’s final start came when he was third to Breeny’s Fella and Shakamaker in the Victoria Cup as 1/2 favourite. He was found to have a cough but also a leg injury which ended his racetrack career and he was retired to Wai Eyre Stud.
Stud career
It was announced in 2013 that he would move to Nevele R Stud. At the time progeny of Christian Cullen had earned $50 million in stakes and as of October 2015 they have won over $75m. His progeny include New Zealand Trotting Cup winner Mainland Banner, Miracle Mile Pace winner Christen Me, Auckland Pacing Cup winner Gotta Go Cullen and A G Hunter Cup winner Stunin Cullen as well as numerous Derby and Oaks winners. He has been the leading sire in both New Zealand and Australia and his service fee at one time reached NZ$25,000.
