Fabiano Caruana emerged as the sole leader after the opening round of the Sinquefield Cup, defeating Jorden van Foreest with white while the other four games finished drawn.
The tournament, which carries a $475,000 prize fund, is also the final event of the Grand Chess Tour before the season-ending Finals, also set to take place in Saint Louis. The four qualifiers for that event will be confirmed by the result of the ten-player single round-robin.
Round 1 results
Among the drawn encounters, Javokhir Sindarov came closest to joining Caruana in the lead. Facing Levon Aronian, the World Championship challenger reached an opposite-coloured bishop endgame with rooks still on the board and established a sizeable advantage.
Sindarov was two pawns ahead at one stage and believed the position should be winning (as he later told Maurice Ashley in the post-game interview).
Commentators, including GMs Peter Svidler and Yasser Seirawan, pointed out that 32.f3?! by Sindarov was a crucial mistake while he tried to convert his two-pawn advantage. The pawn push allowed Black to gain a couple of key tempi with 32...Be6 33.Re4 Bd5. Aronian continued showing good defensive technique until obtaining what might turn out to be a very valuable half point.
Video produced by the Saint Louis Chess Club

Javokhir Sindarov facing Levon Aronian | Photo: Lennart Ootes
The round's only decisive game followed a theoretical variation of the Italian, an opening often seen in elite classical tournaments. Caruana and Van Foreest moved quickly through the early stages before the American adopted an unusual-looking arrangement in which his queen sat on f1, boxed in behind rooks on e1 and e2.
Caruana used more time than his opponent in the early middlegame, but the balance on the clock shifted when Van Foreest was forced into a lengthy think on move 18, spending close to 15 minutes from the roughly 50 he had remaining.
A knight move by the Dutchman soon after, on move 20, proved inaccurate and allowed Caruana to take control. He gained a pawn a bit later and steadily increased the pressure thereafter. Van Foreest resisted, but Caruana converted the extra material with precise technique to secure victory after 55 moves.
Round two will see Caruana take the black pieces against Anish Giri. Van Foreest, meanwhile, will have Black for a second consecutive round when he faces Wesley So on Tuesday.

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