Michael Seward Gregory (16 December 1956 – 19 April 2022) was an English professional darts player, best remembered as the runner-up to Phil Taylor in the 1992 Embassy World Darts Championship final, which went to a tiebreak final leg and is regarded as one of the greatest matches in darts history.

Gregory was also twice runner-up in the Winmau World Masters. Among his tournament wins were the News of the World Championship (1987 and 1988), the Butlins Grand Masters (1984), the MFI World Matchplay (1986), the WDF Europe Cup (1988), the WDC UK Masters (1992 and 1993) and the European Masters (1995). Gregory was also a controversial figure in the 1993 split in darts, first siding with the rebel World Darts Council players in leaving the British Darts Organisation, before rejoining the BDO.

Gregory was one of the top ranked players from the mid-1980s through to the early 1990s, having been seeded in the top four at the World Championships on seven occasions – although he never won the World title.

His major breakthrough was beating John Lowe in the semi-finals of the 1983 British Open in which he finished runner-up to Eric Bristow. He lost again to Bristow in the final of that year's World Masters tournament. He made his World Championship debut in 1984 and reached the quarter-final, losing heavily 0–5 to Jocky Wilson.

Gregory lost at the quarter-final stage of the World Championship in 1987, 1989 and 1993. He made his first semi-final in 1990, losing to Eric Bristow and his only final appearance came in 1992 – when he lost an epic match 5–6 in sets to Taylor. Having missed six darts for the title – two each for double 20, double 8 and double 10, which he has since jokingly referred to as the Bermuda Triangle – the match went all the way to a sudden death leg, which comes when the players reach 5–5 in both sets and legs. It was the first time this had happened in the World Championship's 14-year history and the match is often mentioned in discussions about the greatest darts match; Taylor himself listed this as his greatest ever match. Gregory won the bull-off to throw first in the decider, but had a bounce-out on his first turn and Taylor comfortably sealed the win. Gregory would become the only man to have lost a World Championship final having had darts at double to win, and remained so until Mark McGeeney did so in 2018.

Whilst he was never a World Champion, he won many televised titles of the era, including the 1984 Unipart British Professional (beating both Jocky Wilson and John Lowe), the 1986 MFI World Matchplay, as well as becoming one of only seven players to win the News of the World Darts Championship twice (in 1987 and 1988), joining Tom Barrett (1963–64 and 1964–65) and Eric Bristow (1983 and 1984) as the only other players to win it in consecutive years.

Gregory was a controversial figure in the split in darts, a dispute between the game's governing body, the British Darts Organisation, and the top players. Darts had boomed in the 1980s, with as many as 23 televised events in 1983, but this had steadily diminished to just one by 1989. This reduction in prizemoney and television exposure meant that players were no longer able to make a living from the sport. The top players, their managers and darts equipment manufacturers felt that the BDO were not doing enough to improve the image of darts and attract new sponsors, so they formed the World Darts Council, which eventually became the Professional Darts Corporation. By the end of 1992, the WDC had begun to stage their own tournaments outside the auspices of the BDO. The first of these, the Lada UK Masters, was shown on Anglia Television and was won by Gregory.

At the 1993 Embassy World Championship, the WDC players were ordered to remove their WDC insignia. Later in the tournament, 16 WDC players, including Gregory, issued a statement saying that they would only participate in the 1994 World Championship if it came under the auspices of the WDC, and that they only recognised the WDC as having the authority to sanction their participation in darts tournaments worldwide. The BDO responded by banning the 16 "rebel" WDC players, and any other players or officials who associated with them, from all competitions. This was endorsed at a World Darts Federation meeting in October 1993 and became a worldwide ban. This resulted in four years of litigation, as the WDC sought to overturn the ban.