Avatar of Kirill Stupak
Player Profile

Kirill Stupak GM

S2PAc Minsk Since 2018 (Active) Chess.com ♟♟♟♟♟
50.1% W 40.6% L 9.2% D
Bullet
2881
563W 508L 72D
Blitz
2931
1040W 840L 214D
Rapid
2561
75W 12L 23D

Kirill "S2p" Stupak: The GM With Sleeves

Kirill Stupak, known to the live chess crowd as S2PAc, is a FIDE Grandmaster who seems to run on long endgames, early Sunday mornings, and a healthy amount of rivalry. He arrived around 2018 with what looks like a new account and a very fast learning curve, then spent the years building a board-wide resume of more than 3,000 online games.

His happy place is Rapid, the time control where he can actually think without the board setting on fire. He has turned that into a steady, practical style with a surprisingly dangerous punch.

Rapid, With a Comma

Stupak has made Rapid feel like his home court. His Rapid record is 82 wins, 18 losses, and 29 draws, which is the kind of ratio that makes opponents open with the same mistake twice. His rating arc in the format also shows the climb from a quiet newcomer into a player who expects to win.

Rapid Rating257825262474242223702020: 23872021: 25522022: 25612024: 25612025: 256120202021202220242025

If you want the sharper view, he has also peaked at 2946 (2020-02-12) in Blitz and 2928 (2020-11-04) in Bullet. Those numbers are not a ratings section, they are just landmarks along his trail.

Repertoire With Attitude

One thing that stands out is how often Stupak goes back to trusted opening wells. The Caro-Kann Defense is a perfect example: in his Rapid games as Black, he has a 6-0 record with it, which is the kind of small-sample perfection that makes opponents glance at the screen twice. He also keeps a soft spot for the Czech Defense, especially in Blitz, and the French Defense appears again and again in his Black games.

His opening hit rate is reflected in the board.

Win Rate by Opening0%25%75%100%50%Döry Defense: 53.5% over 215 gamesLondon System: Poisoned Pawn Variation: 54.5% over 202 gamesCzech Defense: 53.6% over 192 gamesCaro-Kann Defense: 52.6% over 154 gamesAmazon Attack: Siberian Attack: 49.2% over 126 gamesAustralian Defense: 47.4% over 114 gamesDöry Defense54%London System: Poisoned…54%Czech Defense54%Caro-Kann Defense53%Amazon Attack: Siberian…49%Australian Defense47%

Favorite Rivals, Favorite Knives

Online Grandmasters can feel like a small town, and Stupak has built a few neighborhoods. His longest online duel is with Fidel Corrales Jimenez, whom he has faced 69 times while collecting 39 wins. He also keeps a long-standing series with Pavel Eljanov, where 14 wins, 14 losses, and seven draws mean the two know each other's engine by heart.

When he plays, he tends to go all the way. His games regularly pass the 80-move mark, and he enters an actual endgame in most of his battles. That endurance, plus an 87.5% comeback rate, makes him extremely annoying to beat.

Best Windows to Face Him

His rhythm has a few patterns, though you might want to ignore them at your own cost:

  • Sunday is his best day, with a win rate above 57%.
  • At 08:00, his win rate jumps past 80%. Play him in the morning if you believe in the impossible.
  • He can also go on a 27-game winning streak, so give him a wide berth.

He is not unkind, the losing streak is just long enough to keep him honest.

Bio last updated 2026-09-08