Washington Nationals pitcher Sean Doolittle will not go to the White House when the World Series champions meet Donald Trump on Monday.

“At the end of the day,” the 33-year-old told the Washington Post, “as much as I wanted to be there with my teammates and share that experience with my teammates, I can’t do it. I just can’t do it.”

Doolittle said his opposition to the president was based on “a lot of things, policies that I disagree with, but at the end of the day it has more to do with the divisive rhetoric and the enabling of conspiracy theories and widening the divide in this country”.

The Nationals clinched their first World Series title in Game 7 in Houston on Wednesday against the Astros, after blowing a two-games-to-none lead with three home losses then coming back from 3-2 down. Doolittle, a closer, took care of business in Game 6, relieving series MVP Stephen Strasburg in a 7-2 victory in Texas.

Trump attended Game 5 in Washington, only to be booed and subjected to chants of “Lock him up”, triggering national debate about the need or otherwise for civility in a polarised society.

People say it’s about respecting the office of the president. He’s done things that maybe don’t respect the office Sean Doolittle

On Saturday the Lincoln biographer, Clinton adviser, Guardian contributor, baseball fan and stringent Trump critic Sidney Blumenthal wrote in an email: “The Red Sox had the curse of the Bambino. The Cubs had the curse of the billy goat. The Nationals had the curse of Trump.

“From the moment he announced he would attend a game they lost three straight World Series games in their own park. Then, they removed themselves from the scene of the curse and won two straight in Houston. About Trump ever entering Nationals Park: Never Again!”

No team based in Washington had won the World Series since 1924. In a euphoric tweet after the team’s victory, Doolittle said the trophy was “v shiny, hard to drink from (we tried), impossible to eat cereal out of, heavier than it looks, can be worn like a hat, still in one piece (barely), says 2019 World Champions on it, IS BACK IN DC AND WE CAN’T WAIT TO SHARE IT WITH YOU.”

The champions paraded through the city on Saturday, to a rally near Capitol Hill. Tens of thousands of fans attended.

The Nationals parade moves past the National Archives on Constitution Avenue, near the National Mall. Photograph: Peter Casey/USA Today Sports

Doolittle told the Post he did not want to distract from teammates who did want to meet the president but said he felt “very strongly about his issues on race relations” and wanted to make a stand for LGBTQ rights. His wife Eireann Dolan – with whom he said he had done “work with refugees”, making Trump’s infamous “shithole countries” remark particularly painful – has two mothers, he said.

“I want to show support for them,” Doolittle said. “I think that’s an important part of ally-ship, and I don’t want to turn my back on them.

“I have a brother-in-law who has autism, and [Trump] is a guy that mocked a disabled reporter. How would I explain that to him that I hung out with somebody who mocked the way that he talked, or the way that he moves his hands? I can’t get past that stuff.”

Trump infamously mocked Serge Kovaleski in 2015, over the New York Times reporter’s work on the billionaire’s dubious claims about his experiences on 9/11. Kovaleski has a condition, arthrogryposis, which affects the movement of his arms. The Times called Trump’s mockery “outrageous”.

Doolittle said he had studied how other champions handled their decisions not to visit the White House. Winners from the NBA, NHL and NFL have refused to go. Trump has clashed personally with many, notably last summer with Megan Rapinoe, the star player on the US team which won the Women’s World Cup.

Doolittle indicated that if the president comes out swinging – and tweeting – he will not be tempted to throw any beanballs back.

“I don’t want to get mad online,” he said. “I want people to know that I put thought into this and, at the end of the day, I just can’t go.”

He added: “People say you should go because it’s about respecting the office of the president. And I think over the course of his time in office he’s done a lot of things that maybe don’t respect the office.”