WESLEY So downed Georgian Baadur Jobava with black in the sixth round early Saturday to boost his drive in the all-Grandmaster Tata Steels Masters in Rotterdam, the Netherlands.
The Cavite-born So, now representing the United States, was quality up and was threatening mate when Jobava resigned after 39 moves of a Giuoco Piano, giving the former whiz kid 4.0 points and a share of second in the 14-player tournament.
Tied with So, half a point behind Ukrainian pacesetter Vassily Ivanchuk were Norweigian world champion Magnus Carlsen and Pole Radoslaw Wojstaszek.
Ivanchuk kept top spot with 4.5 points despite being held to a draw by Croatian Ivan Saric.
Rebounding from a poor start, Carlsen (Elo 2860) trounced world No. 2 Fabiano Caruana (2820) of Italy in 39 moves of a Sicilian (Rossolimo variation) for his third straight win.
Wojstaszek, who stunned Carlsen and Caruana in the third and fifth round, respectively, settled for a draw with women’s world champion Hou Yifan.
His victory over Jobava, who slumped to his fourth straight defeat, pushed So’s live rating to a personal-high 2781.4, good for ninth in the world rankings.
So pulled away from Hiraku Nakamura (2776) and inched closer toward No. 8 Armenian Levon Aronian (2782.9).
Aronian drew with Dutch Loek Van Wely and was near the cellar at 2.0 points.
So was battling Azerbaijan’s Teimour Radjabov (3.0) in the seventh round that started Saturday night. Other matches pitted Carlsen against Hou (2.0); Saric against French Maxime Vachier-Lagrave (3.5); Giri (3.5) against Ivanchuk; Wojtaszek against Jobava (0.5); and Aronian against Caruana.