Following our Team Selected Seeding blog post, where we briefly touched on a new approach to adjusted seeding throughout the tournament, we are excited to share more details about this process.
ESL Live Ratings
ESL Live Ratings method was first introduced at the IEM Katowice 2019 Major. The feedback we received was largely positive; however, we always had bigger plans for this system and have since worked on several improvements.
Majority of tournaments using a Swiss format historically use a set pre-event seeding, we believe that combining Team Selected Seeding with our improved Live Ratings system yields better accuracy. Team Selected Seeding establishes baseline ratings (e.g., 1.03 for the highest-ranked team, 2.70 for the second-best ranked team), which then translate into the initial tournament seeding (1-16).
For the first round matchups, we used standard bracket pairings (1 vs 16, 2 vs 15) instead of the pairing method used at the Majors (1 vs 9, 2 vs 10).
Following the first round, matchups in the Swiss format are always determined based on the current W-L record (e.g., winners of round 1 are grouped together and losers are placed in a separate pool). At the Majors, the Buchholz system is used for tie-breaking, but we will once again be utilising the ESL Live Ratings method. While Buchholz's effectiveness is limited in the early stages due to the small sample size. We believe that ESL Live Ratings will provide a more accurate and dynamic approach throughout the entire tournament.
In ESL Pro League, after the first round, teams will be paired based on their updated ESL Live Ratings, with the restriction that no rematches can occur. Previously, during IEM Katowice 2019, matchups were determined solely by their updated seed rather than Live Rating values, which is one of the key improvements we have since implemented.
Here is a quick example showcasing how this system works:
- Seed #1, Live Rating: 1.99
- Seed #2, Live Rating: 2.00
- Seed #3, Live Rating: 2.01
- Seed #4, Live Rating: 4.00
- Seed #5, Live Rating: 5.00
- Seed #6, Live Rating: 6.99
- Seed #7, Live Rating: 7.00
- Seed #8, Live Rating: 7.01
Scenario: Seed 6 already played against Seeds 2 and 3, no other rematches are possible.
- If we used seeding to determine matchups, the best matchups would be 1 vs 8, 2 vs 7, 3 vs 5, 4 vs 6, with a total deviation of 2 seeds.
- If we used Live Ratings instead, the best matchups would be 1 vs 6, 2 vs 8, 3 vs 7,4 vs 5, with a total deviation of 4 seeds, because 1, 2, 3 and 6, 7, 8 are almost identical in skill based on their Live Ratings.
Detailed explanation:
Only teams that are in the same result-pool (e.g. 2 win 1 loss pool) can play against each other.
No teams that have played against each other before in the same Swiss System can play against each other again.
The quality of all matches is determined based on the live ratings of the teams:
- The average live-rating of all teams in the current result-pool is being used as a basis. The ideal opponent for every team is the team whose live-rating is equally distant from the average live-rating but in the other direction
- Example: if the average live-rating of the 1:1 result-pool is 8 and Team Green has a live-rating of 5 (=8-3), then the ideal opponent for Team Green would have a live-rating of 11 (=8+3).
- The difference in live-rating between ideal opponent and actual opponent is squared. This is to prefer many small gaps over one large gap.
- Example: A match with a difference of 2 from ideal will contribute 2²=4 to the quality.
- The quality of each option for a match-day in one result-pool is determined by the sum of these squared numbers (match-days with one or more rematches are being discarded, as by point 2.)
- Example: If three out of four matches have a difference of 0 and the other one has a difference of 2 (total difference of 2), that will result in a total quality score of 0²+0²+0²+2²=4.
- If three matches have a difference of 1 and the other one has a difference of 0 (total difference of 3), that will result in a total quality score of 1²+1²+1²+0²=3.
- The matchday with the lowest such number will be used for the match-day in the result-pool in question.
- Example: In the above example under 3., the second option would be preferred over the first.
Future Improvements:
There are many more improvements we have in mind for the future, but we want to ensure we are not introducing too many changes all at once. Looking ahead, we plan to assess whether the formula for the rating adjustments can be further optimized and possibly implement a system to factor in actual match results; for example, a team losing 2:0 could be weighted differently than if they were to lose 2:1.
There are still numerous ways to enhance the system further and we believe it would be beneficial to share the exact formula and process with the community. This would encourage community members to experiment with it, utilise it at their own events, and ultimately help refine it. The formula used to adjust this rating is 5*(1-1/(1+10^((X-8)/10))), where “X” is the difference by which your opponent’s live rating is better than your own (negative numbers will indicate that their live rating is worse than your own).
We strongly believe this system has the potential to improve any Swiss format and we’re looking forward to following the community reactions as it plays out during Stage 1 and 2 of the upcoming season.
ESL Pro League Season 21Current Live Ratings
| Seed | Team Name | ESL Live Rating (“ELO”) |
|---|---|---|
| 1 |  Eternal Fire | 1.00 |
| 2 |  paiN
| 2.23 |
| 3 |  3DMAX | 3.21 |
| 4 |  FURIA | 3.75 |
| 5 |  GamerLegion | 4.29 |
| 6 |  HEROIC | 4.92 |
| 7 |  MIBR | 6.62 |
| 8 |  FlyQuest | 8.00 |
| 9 |  M80 | 9.00 |
| 10 |  Nemiga | 9.23 |
| 11 |  SAW | 9.23 |
| 12 |  NRG | 11.5 |
| 13 |  Lynn Vision | 11.93 |
| 14 |  TYLOO | 12.64 |
| 15 |  Housebets | 14.33 |
| 16 |  Mindfreak | 15.00 |
Outro
Read More about Live Ratings and Team Selected Seeding in our 2025 Rulebook Update and Tournament Seeding for ESL Pro League updates.
To keep up to date with our plans for 2025 and not miss any important updates, as always, make sure to sign up for our newsletter and follow ESLCS on X, Instagram, and Facebook.
