Tsarsitalidis Konstantinos: The Comeback King of Online Chess
From 962 to 2800: A Wild Ride
Tsarsitalidis Konstantinos, better known online as kontsarsi2004, started his chess journey in June 2019 with a Daily rating of just 962. That humble beginning did not last long. By 2020 he was climbing rapidly, and in 2026 he reached a peak Blitz rating of 2818 and a peak Bullet rating of 2774. It is the kind of trajectory that makes opening databases blush.
He favors Rapid chess, and the numbers agree. His strength adjusted win rate in Rapid sits at an excellent 64.8%, the highest of any time control in his portfolio.
Openings and Style
Konstantinos is a lifelong student of the Sicilian Defense, with a special fondness for the sharp Najdorf Variation. His Daily record in the Najdorf is impressive, and he also enjoys the tricky Blackburne Shilling Gambit and the solid Caro-Kann Defense.
One quirk stands out: as White he has a 97% win rate in the Barnes Defense, yet as Black he has lost all 26 of his Barnes Defense games. The lesson is simple. Only play the Barnes Defense when it is your move first.
Rapid Growth
His Rapid rating climbed from 1200 in early 2020 to a peak of 2327 in December 2021. While he plays fewer Rapid games than Blitz or Bullet, his conversion rate is outstanding. He also punishes lower rated opposition, winning 69% of those encounters.
Rivalries and Rivals
No biography is complete without rivals. His most frequent opponent is Pawel‚ Dudzinski, who has faced him 22 times. The series against WarlordX is remarkably balanced, while diamondmaster3000 holds a narrow edge. The toughest assignment is Alexey Kislinsky, who leads their head to head series 12 wins to 2. Some opponents are simply kryptonite.
The Numbers Behind the Name
- A 17 game winning streak and a 45 game losing streak. He has experienced both heaven and the abyss.
- A 84.27% comeback rate, meaning he rarely goes down without a fight.
- His best playing hour is 05:00. Early birds and insomniacs both claim him.
- Queen checks dominate. In over 5,600 analyzed games, the queen is his most common checking piece.
- His average win takes about 77 moves, showing patience is part of his toolkit.
- When he gets the first check, he wins 55% of the time. When his opponent checks first, that drops to 40%.
- Peak Blitz rating: 2818 (2026-04-16). Peak Rapid rating: 2327 (2021-12-25).