Moscow Flyer never won a Bumper. He came third in two of his four bumpers, but never was first past the post. He was quickly changed to hurdling after the usual one season of competing in bumpers. He started off as a close to top-class hurdler. He won the 2000 December Festival Hurdle claiming the notable scalp of Istabraq who fell at the last when in contention. Moscow Flyer himself fell two out in that season's Grade 1 AIG Europe Champion Hurdle when in contention. He was entered in the 2001 Champion Hurdle but Foot and Mouth caused the Cheltenham Festival to be abandoned.
2001/2002 season: Novice chases
Moscow Flyer returned in the 2001/2002 season as a novice chaser. His record coming into the Arkle Challenge Trophy was mixed. He had won three races but also fallen twice. Consequently, Seebald went off as favourite. However, Moscow Flyer won easily by four lengths. That year's Champion Hurdle was won with a Racing Post Rating four below Moscow Flyer's highest rating of 170 achieved the previous April at Punchestown.
2002/2003 season: steeplechases
Moscow Flyer returned to the Festival for the 2003 Queen Mother Champion Chase having won four races out of five that season. In his only defeat, reigning champion Flagship Uberalles made a very bad mistake at one fence in the Tingle Creek Chase at Sandown. Moscow Flyer was behind him and was unable to avoid running into the back of him and unshipping Barry Geraghty. He started as a short-priced 7/4 favourite for the Champion Chase and won by 7 lengths.
2003/2004 season
Moscow Flyer won his first three races of the season and again was the favourite for the Queen Mother Champion Chase. He started at 5/6 while his main rival Azertyuiop was the 15/8 second favourite. His rival had won the previous season's Arkle Challenge Trophy and the race was seen as a match between the two despite the presence of Flagship Uberalles and Tiutchev. However, Moscow Flyer made a mistake four out and gave Geraghty no chance of staying on him. Azertyuiop went on to an easy victory.
2004/2005 season
Moscow Flyer returned the next year to try to be the first horse in many years to regain the Queen Mother Champion Chase. He retained his Tingle Creek Chase crown and broke his odd record of falling every four races. Opposing him were Azertyuiop at 2/1 and a new challenger in the previous year's Arkle Challenge Trophy winner Well Chief at 7/2. Strong betting support on the day made Moscow Flyer the 6/4 favourite. Azertyuiop made a mistake at the water jump and although he came third he was not in contention for the last half of the race. Moscow Flyer held off the challenge of Well Chief to the cheers of his fans. His subsequent win at Aintree was his seventh in a row. Moscow Flyer lost by a short-head at Punchestown to Rathgar Beau on 26 April 2005. Many thought that there was a dead heat, but the stewards awarded the race to Rathgar Beau. This horse was the first to beat Moscow Flyer when he didn't fall since Colonel Yeagar on 18 April 2001.
2005/2006 season
Moscow Flyer was aimed to win the Queen Mother Champion Chase for a third time. He suffered another defeat to Central House at Navan in the Fortria Chase, a defeat clear from the landing after the last, that silenced the crowd. A further defeat followed in December by Hi Cloy at Leopardstown in a race best remembered for Roger Loughran's mistake as to the whereabouts of the finishing line. Subsequently, Moscow Flyer ran in the Champion Chase, entering the field without a win that year. He went off at 5/1 and finished fifth. He was retired immediately after the race.
Retirement
Moscow Flyer spent some time as a pin-up pony for retired racehorses in Ireland. He was in good health on a return to Sandown in 2006 for a parade before the Tingle Creek—and again before the Champion Chase at Cheltenham. In April 2007, in the closing race of the Punchestown Festival, a 2-Mile Charity Flat Race, Moscow Flyer recorded his first ever flat victory. Ridden by the Irish 18-year-old Kate Harrington, Moscow won comfortably and was giving a rousing reception in the winners' enclosure postrace. Moscow Flyer was in retirement with the Irish Horse Welfare Trust at their farm in Woodenbridge, Co Wicklow. He made public appearances for the Charity to help promote the work of the equine welfare charity and had many visitors throughout the year. Moscow Flyer was offered a place at the Irish National Stud in County Kildare, Ireland in spring 2012. His owner, former trainer, and staff at the IHWT decided that this was a great opportunity to afford more people a chance to see a true champion racehorse and an ambassador for equine welfare. He resided at the national stud with a number of other famous racehorses until October 2016 when his death was announced at the age of 22.