Jiří Jirka, International Master
Meet International Master Jiří Jirka
International Master Jiří Jirka (often romanized as Jiri Jirka for keyboards and search engines) plays online as Krvelacny_krecek, a Czech username that translates, roughly and menacingly, to something like "bloodthirsty hamster." The branding is accurate. Beneath the FIDE International Master title and the adorable exterior lives a 1.d4 player of near-religious conviction who has haunted the online chess blitz boards since April 2020, even though his profile politely lists Rapid as the preferred time control.
Career Highlights
The ledger shows more than 2,300 recorded games, and all but about three dozen of them are blitz. From a first-month floor around 1950, he climbed through a strong 2024 and a monster 2025, peaking at 2673 (2026-08-12) in August 2026. The chart below is the story of a hamster that refused to stay small.
His rapid sample is small but glossy: 24 wins, 7 losses, 3 draws, with a 2438 peak back in early 2021. Bullet is even better comedy: two games played, one win, one draw, and a peak of 2694 (2021-05-22). Arguably the most efficient format switch in online chess history.
Playing Style: The Endgame Grinder
Jiri's wins are marathons, averaging about 73 moves, and more than 84% of his games march into an endgame. He rarely resigns early, waits until roughly move eight for his first capture, and treats a worse position as a friendly suggestion rather than a verdict. His comeback rate sits near 88%, he still wins about half the games where he drops a piece, and only about a third of his losses are one-sided. When the hamster loses, it at least loses while chewing on your ankle.
Opening Repertoire: It All Starts With 1.d4
As White, the first move is d4 in essentially every recorded game. The signature weapon is the Slav Defense Bonet Gambit, an offbeat line he has played 135 times in blitz for a 63.7% win rate, which functions as a jump scare in opening form. Around it sits a serious toolkit: Grünfeld Defense Counterthrust structures at 64% wins, a Catalan Opening whose Open Defense converts near 66%, plus the Benoni Defense, the delayed fianchetto King's Indian, and the London System Poisoned Pawn for seasoning.
As Black he trusts the Ruy Lopez, notably the Bird Variation at 57% wins, the Scotch Game above 60%, and a wardrobe of Slav setups. He also experiments with the Blackburne Shilling Gambit, an investment currently returning closer to lottery scratcher yields than compound interest.
The entire empire rests on this:
Rivalries and Memorable Matchups
Every hamster has its hawk. Jiří has faced Sinisa S Popov 23 times and trails that series 7-13-3, making popovbm the closest thing to kryptonite in the database. The food chain flips elsewhere: Spiderman-83 has been caught 15 times in 18 games against only 2 losses, and Nitenslo offers little refuge either, dropping 10 of 12 encounters. Somewhere out there, one rival is doing victory laps while two others are doing cardio.
Quick Facts and Quirks
- At 4 AM he wins 100% of his games; at 1 AM he wins 0%. The math is clear: one extra hour of sleep is worth a whole rating class.
- Saturday is his strongest day of the week, Thursday his weakest.
- Longest winning streak: 10 games. He is currently riding a 9-game heater.
- Never lost by stalemate, but has rescued two draws with one.
- The queen is his favorite checking piece, though rooks took over the shift in 2026.
- Statistically, his scariest opponents are the ones rated exactly equal to him.
- Casual games are where the hamster truly frolics: his casual win rate runs about 47 points above his rated one.