The battle raging around Minnetonka grandmaster Wesley So has taken another turn, with his estranged mother writing a lengthy statement explaining why she arrived unannounced on the eve of the U.S. Chess Championship in St. Louis.

Eleanor So said she made the trip from Toronto, where she lives, because access to her son has been blocked by the Minnetonka family he now lives with. She said she and her family “are at the end of our rope and don’t know how to proceed.”

Wesley So has said that his mother and aunt harassed him during their visit and that the tension and turmoil caused him to lose focus, play poorly, and miss a chance at the national title.

“It’s clear they have one aim, one goal, to get me to go back to school and they don’t care about my tournament here,” he said last Friday in St. Louis. “Leave me alone during the tournament. We can talk about this later.”

Wesley So, 21, has had a quick ascent to the highest level of the chess world and is currently ranked No. 8.

He has not lived with his parents since he was 15 or 16 years old and they moved with his two sisters from their native Philippines to Canada. Last October, he left Webster University in suburban St. Louis and moved in with the Minnetonka family, which he now calls “my family.”

In a statement given to the website Chessdom, Eleanor So cast the Minnetonka mother, Lotis Key, as manipulative and as responsible for a change in her son’s behavior.

“He became cold and distant to his friends and family,” she wrote. “For the first time, he did not even call or wrote [sic] me on my birthday. This is not like him at all.”

She said that “since someone is blocking us access to our own son, we had to try and see him in person to help him.”

Eleanor So said she contacted Paul Truong, the coach of the chess team at Webster, which her son attended on a chess scholarship. She said she asked Truong about the U.S. Championship tournament, he provided them with a link to the tournament website, and they made their plans accordingly.

Eleanor So said her son was happy to see her and she provided Chessdom with photos showing them posing together and smiling during the visit.

Key could not be reached for comment Tuesday. In an interview Friday in St. Louis, she said the visit was filled with tension and that Wesley told her that in a private meeting his mother made threats, including cutting contact with his sisters, if he didn’t return to college.

On the second day of the tournament their differences spilled into public view. Wesley So said that as he left the playing hall Eleanor So tried to grab his arm when he wouldn’t go with her and she yelled at him. Key and Wesley So called the tournament site later that night to report the incident. The staffer who took the phone call wrote in an e-mail to the tournament’s chief arbiter that Wesley So said that Eleanor So and the aunt “were harassing him after the game and trying to force him to go somewhere with them.” So asked that they be banned from the site, which they were.

The next day, Wesley So had the first of his four losses in the 11-round tournament. He finished in third place.