Dr Ian Plummer
Technical
How to Arrange an AllPlayAll
Tournament
John Riches indicates how to arrange an allplayall
draw, which he recommends for American Blocks.
For ten players AJ. Just keep A constant and rotate the
other nine letters, starting with them listed down the lefthand column and
back up the righthand column (see appendix for detail). The numbers
represent rounds and the letters represent the players.
1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 
9. 
AJ 
AI 
AH 
AG 
AF 
AE 
AD 
AC 
AB 
BI 
JH 
IG 
HF 
GE 
FD 
EC 
DB 
CJ 
CH 
BG 
JF 
IE 
HD 
GC 
FB 
EJ 
DI 
DG 
CF 
BE 
JD 
IC 
HB 
GJ 
FI 
EH 
EF 
DE 
CD 
BC 
JB 
IJ 
HI 
GH 
FG 
For a chess tournament where the firstnamed player has the white pieces,
in order to ensure that each player has a colour distribution as even as possible,
player A would alternate from the lefthand column to the righthand column,
and the nine rounds listed above would be played in (for example) the order
1, 6, 2, 7, 3, 8, 4, 9, 5.
The same system works for any even number of players. For an odd number
of players one of the letters is designated as the "bye".
If the players are listed as A, B, C ... in order of strength, the above draw
has the top two players meeting each other in the final round, which is a good
thing. Many people do not realise the important of seeding an allplayall
(or "American") event to ensure that the top players do not meet in early rounds. If
they meet in early rounds it destroys further interest in the event because
once they have played each other the almost certain winner will be apparent;
and it also tends to decrease the number of spectators and increase the number
of forfeits and withdrawals.
Appendix
More detail on creating the table for an even number of players. In this example
the players are numbered 110
1. Allocate each player a number, then list the players in pairs with the
numbers going down the lefthand column and back up the righthand column.
For 10 players there will be 5 rows as follows: 110 29 38 47 56. This
represents the draw for round 1.
1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 
9. 
110 








29 








38 








47 








56 








2. For round 2 leave number 10 unchanged and add one on to each of the other
numbers, but you can have only one number 10, so when you add one onto 9 call
it 1, not 10. This gives:
1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 
9. 
110 
210 







29 
31 







38 
49 







47 
58 







56 
67 







3. For round 3 repeat the same process, leaving 10 unchanged and adding one
onto each of the other nine numbers, except that 9+1=1, not 10.
1. 
2. 
3. 
4. 
5. 
6. 
7. 
8. 
9. 
110 
210 
310 
410 
510 
610 
710 
810 
910 
29 
31 
42 
53 
64 
75 
86 
97 
18 
38 
49 
51 
62 
73 
84 
95 
16 
27 
47 
58 
69 
71 
82 
93 
14 
25 
36 
56 
67 
78 
89 
91 
12 
23 
34 
45 
Author: John
Riches
All rights reserved © 2004
