Rauf Kasimov: The Blitz Marathoner
Rauf Kasimov, who competes online as KasimovR21, is a FIDE Candidate Master with a serious appetite for marathon sessions. His preferred battlefield is blitz, where he has played nearly 10,000 rated games since 2023. Along the way he has cracked the 3000 barrier in that time control, a rare online achievement for any player.
From Candidate Master to Online Headliner
Kasimov's official title is Candidate Master, but his online numbers tell the story of a player who thrives on the clock. The chart below shows his blitz climb from 2023 through 2026, a journey that includes explosive surges, stubborn slumps, and an unmistakable upward trend.
He has also made serious noise in bullet, reaching 2851 (2026-08-03), while his blitz peak sits at 3005 (2026-08-01). His longest winning streak is 19 games, and even a 14 game losing streak never kept him away from the board for long.
Style and Opening Repertoire
Kasimov is not afraid to play main lines. His online games are packed with the Caro-Kann Defense, the Petrov's Defense, and the Four Knights Game. He also dips into sharp Sicilian structures and has a soft spot for the Amazon Attack, both as White and Black.
His stats show a fighter's mentality: he rarely resigns early, reaches the endgame in almost 79 percent of games, and keeps a 43 percent win rate even after losing a piece. A recurring theme is the Sicilian Defense, where he often looks for unbalanced play and counterattacking chances.
Rivalries and Repeat Battles
No online career is complete without familiar faces. Kasimov's most played opponent is ClassAct01, with 55 meetings. He also has a deep history with Robby Adamson and a notably strong record against b_jumavaev, winning 33 of 40 encounters. Against saidusd he has been nearly unstoppable, collecting 26 wins in 28 games.
The Marathon Numbers
- More than 12,000 rated online games analyzed.
- Favorite time control: blitz, with over 9,700 blitz games.
- Best results tend to come at 21:00, making him a true night owl.
- White win rate is 47 percent, Black win rate is 42 percent, proof he keeps fighting from both colors.
A Repertoire Snapshot
The following moves represent the kind of flexible, tactical Sicilian structure Kasimov often reaches in his online battles.
Rauf Kasimov is proof that online chess rewards endurance. Whether he is outlasting rivals in blitz, blitzing through bullet, or grinding out endgames, KasimovR21 remains one of the most active and entertaining Candidate Masters on the platform.