The World Professional Billiards and Snooker Association (WPBSA), the governing body for professional snooker, first introduced a ranking system for professional players in 1976, with the aim of seeding players for the World Snooker Championship. The reigning champion would be automatically seeded first, the losing finalist from the previous year seeded second, and the other seedings based on the ranking list. Initially, the rankings were based on performances in the preceding three world championships. The 1983–84 snooker world rankings were the first to take tournaments other than the world championship into account and several additional tournaments were designated as ranking tournaments over the following years. The list for the 1986–87 snooker season was the first to only take account of results over two seasons and the rankings for 1990–91 were also based on results from the preceding two seasons.

1990 World Snooker Championship winner Stephen Hendry took first place in the 1990–91 ranking list, followed by Steve Davis. Davis, who had held the number one ranking since the 1983–84 list, withdrew from three ranking events held outside of the UK in the 1989–90 season. He commented that he felt that the increase in the number of ranking events was too rapid and said that "I won't jeopardize my form just for the sake of staying at number one. If I lose my number one place, that's the price I have to pay." The other seven players managed by Barry Hearn's Matchroom company also boycotted the 1989 Dubai Classic. Because of this, a number of "non-tournament" players, usually only allowed to play in the World Championship, were given places in the Dubai Classic. John Parrott was placed third, down one place from the previous season, and Jimmy White stayed in fourth. Doug Mountjoy, who had won the 1988 UK Championship and the 1989 Classic to become the only player apart from Davis to win successive ranking titles, rose five places to fifth.

The top 16 in the rankings were exempted from the qualifying rounds for the World Snooker Championship and were included in certain invitational events. Martin Clark, at 12th, joined the top 16 for the first time. Former world number three Neal Foulds gained seven places, to 13th. Alex Higgins was ranked 14th in the original list for the season, having been 24th the year before, but was docked 25 points and banned from competing for ten months in July 1990. These penalties were imposed by the WPBSA following a hearing conducted for the Association by Gavin Lightman, a barrister, which considered several incidents including Higgins punching a press officer, threatening to arrange for fellow player Dennis Taylor to be shot, and insulting both Taylor and WPBSA chairman John Spencer. This meant that Alain Robidoux gained 16th place. Cliff Thorburn, Joe Johnson and Tony Knowles were the three players to drop out of the top 16.

Points tariff and basis of ranking +Points tariff contributing to the Snooker world rankings 1990–91Placing1989 and 1990 world championshipsOther ranking tournaments 1988–89 and 1990–91Champion 10 6 Runner-up 8 5 Losing semi-finalist 6 4 Losing quarter-finalist 4 3 Last 16 loser 2 2 Last 32 loser 1 ranking point or 2 merit points1Final qualifying round loser 2 merit points 1 merit point Penultimate qualifying round loser 1 merit point 1 A point Antepenultimate qualifying round loser 1 A point Frames won counted Preliminary round loser Frames won counted –

Ranking was determined as follows: By number of ranking points. If players had an equal number of ranking points, precedence was given to the player with the better performances in the later season. If players were still equal, merit points were considered. If they were still tied, precedence was given to the player with the better performances in the later season. If players were still equal, A points were considered. If they were still tied, precedence was given to the player with the better performances in the later season. If players were still equal, frames won were considered. If they were still tied, precedence was given the player with the better performances in the later season.

Rankings Key: "(New)" denotes a player that was a new professional for 1989–90. "(NT)" denotes a non-tournament player, i.e. a player who was permitted to enter the world championship but no other tournaments in 1990–91. "N" denotes that as a non-tournament player, the player was not eligible to enter. "–" denotes that the player did not compete in the tournament. "X" denotes that the player was banned from competing in the tournament. "PL" denotes that the player lost in the professional play-offs.

+Snooker world rankings 1990–91 Ranking Name 1988–89 season 1989–90 season Ranking points Merit A points Frames IO GP CM UK Cl EO BO WC HK AO IO GP DC UK Cl BO EO WC 1 214532263652661051069100 2 66540– 310––66–5424667100 3 01333648103242206654200 4 536104144032–3022848200 5 12266221220350023241300 6033425041410–4010436500 7 12400444611103110235400 8 41121– 54010532111234200 9 41211001112020644232400 10 343211023023–2120029500 11 201242222321–2001228300 12 00113330231121231027600 13 120110203121–1033425500 14 10232212220120201225400 15 310010661101–0110224600 16 14000210104213021123430 17 31122230010302012023800 18 X X3343200001–110042270019 01010101440114200121430 20 21102001202200331121600 21 12022010022302020221800 22 01005002121011301119610 23 11011011510011301018700 24 000100300200322201161100 25 21001001101001161016900 26 100120020310014010161000 27 310300201210210000161100 28 02211120103011000116800 29 001202000004400011151010 30 11001010021021210114800 31 01100302101010102114800 32 (New) – – – – – – – – 051410010012330 33 00120100001003012112640 3412001111011100020012900 35 00000000232211000011850 36 000201121100200010111100 37 230101000000011110111200 38 (New) – – – – – – – – 004120003010420 39 00200000010110500010760 40 00100011000000210410560 41 11110002020000110010640 42 (New) – – – – – – – – 10300130008210 43 0000211000001000218840 44 20202000000000101081130 45 10000000200100030071125 46 00000010002000040075517 47 1000020000001010207670 48 00110010010000003074710 49 02000000000030100061140 50 00200000310000000069510 51 0301000000000010016870 52 2000030000001000006103053 0000310100000001006770 54 (New) – – – – – – – – 11000200015226 55 21100–00000010000051130 56 1010011000000001005850 57 102001100000000000596058 0000010010011000004862 59 00000120001000000041060 60 00000000000000210035417 61 00000100000000002034516 62 0001000100000100003870 63 00000000000110000025614 64 (New) – – – – – – – – 000000002022411 65 000000000002000000221018 66 0000000000020000002141167 00000000NNNN2NNNN02010 68 0001000000000100002790 69 00000010001000000024120 70 00000100000000010023723 71 00100000100000000022133 72 0200000000000000002890 73 0010100000000000002550 74 0000000001000000001990 75 0000000000000001001980 76 00000000000000001018513 77 00000000010000000015626 78 00000000000010000014432 79 0000000000100000001481780 (New) – – – – – – – – 00100000001338 81 00000000000100000013813 82 (New) – – – – – – – – 10000000001247 83 (New) – – – – – – – – 000000100012314 84 0000100000000000001878 85 10000000000000000017519 86 0000100000000000001678 87 00001 000000000000015120 88 0010000000000000001112689 00001000000000000010937 90 00000000000000000001080 91 00000000000000000007722 92 00000000000000000006513 93 00000000000000000006533 94 0000000000000000000661895 00000000000000000006614 96 00000000000000000005106 97 0501111021013115110500 98 (New) – – – – – – – – 000000000004212 99 00000000000000000004140 100 00000000000000000004537 101 00000000000000000003529 102 00000000000000000002632103000000000000000000021022105 00000000000000000002819104 00000000000000000002822 106 00000000000000000002529 107 000000000000000000021027 108 00000000000000000002525 109 (New) – – – – – – – – 00000000000174 110 00000000000000000001731 111 00000000000000000001723 112 00000000000000000001635 113 00000000000000000001630 114 00000000000000000001345 115 00000000000000000001339 116 00000000000000000001823 11700000000000000000001828 118 00000000000000000001614 119 (NT) (PL) 00000000000000000001532 120 (NT) (PL) 00000000000000000001532121 (NT) (PL) 00000000000000000001441 122 (NT) (PL) 00000000000000000001325 123 (NT) (PL) 00000000000000000001332 124 (NT) NNN N N N N0NNNN0NNNN001020 125 (NT)00000000000000000000732 126 (NT) (PL) 00000000NNNN0NNNN000711 127 (NT) (PL) 00000000000000000000621 128 (NT) (PL) 00000000000000000000532 129 (NT) 00000000000000000000529 130 (NT) 00000000NNNN0NNNN000324 131 (NT) 00000000000000000000238 132 (NT)00000000NNNN0NNNN000220 133 (NT) 00000000NNNN0NNNN000210 134 (NT) NNN N N N NN0NNN0NNNN00013 135 (NT) NNN N N N N0NNNNNNNNN000120 136 (NT)00000000NNNN0NNNN000113 137 (NT) 00000000NNNN0NNNN000112 138 (NT) 00000000NNNNNNNNN000112 139 (NT) 00000000NNNNNNNNN00007 140 (NT) NNN N N N N0NNNNNNNNN00004 141 (NT) NNN N N N N0NNNN0NNNN00003 142 (NT) NNN N N N N0NNNNNNNNN00000 143 (NT) NNN N N N N0NNNNNNNNN00000 144 (NT) NNN N N N N0NNNNNNNNN00000 145 (NT) NNN N N N N0NNNNNNNNN00000 146 (NT) 0000000000000000000000 147 (NT) NNN N N N N0NNNNNNNNN00000 148 (NT) NNN N N N N0NNNNNNNNN00000 149 (NT) NNN N N N N0NNNNNNNNN00000 150 (NT) NNN N N N N0NNNNNNNNN00000 151 (NT)00000000NNNNNNNNN00000 152 (NT) NNN N N N N0NNNNNNNNN00000 153 (NT)NNN N N N N0NNNNNNNNN00000 154 (NT)NNN N N N N0NNNNNNNNN00000 155 (NT)NNN N N N N0NNNNNNNNN00000 156 (NT)0000000000000000000000 157 (NT)NNN N N N N–NNNNNNNNN00000 158 (NT)0000000000000000000000

Notes

References

Books