Grandmaster Wesley So stumbled in his first set assignment against former world champion and world No. 1 Magnus Carlsen in their title series in the Champions Chess Tour Finals on Friday, Dec. 15, in Toronto, Canada.

The Philippine-born So was held to a draw in their first two matches before the Norwegian superstar found himself at an advantage and prevailed in the pivotal third match with the black pieces played in a sharp Sicilian battle.

So, who now plays for the United States, attempted to regain his composure but could only manage a draw in the fourth match to give Carlsen the 2.5-1.5 triumph.

“It’s kind of inexcusable to lose a white game in a short match,” said So, referring to his third-match loss.

The set victory put Carlsen a win away from clinching his third title and the $200,000 cash purse.

“The way that I beat him is that I just, you know, I hustle him. I use his sort of lack of aggression against him,” Carlsen said.

But expect So to launch a comeback to extend the best-of-three sets series into a decider, having defeated Carlsen in the eliminations a few days before.