NEW YORK — Washington third baseman Anthony Rendon became a free agent Thursday, a day after homering to spark Washington’s seventh-inning comeback in Game 7 of the World Series.

Houston pitcher Gerrit Cole also went free after warming up in the bullpen but never getting into the season finale.

And Nationals pitcher Stephen Strasburg, the World Series MVP, could be joining them in the next few days. He has the right to opt out of his contract, which has $100 million over four years remaining.

Baseball’s business season starts shortly after the final out.

“I think it’s hard to kind of fast-forward,” Astros Manager AJ Hinch said. “Seasons end really fast. I don’t care if you get all the way to the seventh game of the World Series. It’s all of a sudden – boom! – it’s over.”

Cole, Rendon and Strasburg all are represented by Scott Boras, known for slow, methodical negotiations. Last winter, he reached outfielder Bryce Harper’s $330 million, 13-year contract with Philadelphia on Feb. 28.

Cole, a 29-year-old right-hander who went 20-5 this year, is expected to get a record contract for a pitcher, topping David Price’s $217 million, seven-year deal with Boston before the 2016 season and Justin Verlander’s $31.33 million average salary under a three-year deal with the Astros that started in 2019.

Cole tweeted a letter Thursday praising Houston fans.

“Before I became an Astro I didn’t know much about Houston, but after just two years you have made it feel like home,” he wrote. “This is a relationship between a team and … fans like no other that I know.”

Strasburg, a 31-year-old right-hander, just finished the third season of a $175 million deal and at 18-6 also is coming off his best season. Rendon led the major leagues with 126 RBI while hitting .319 with 34 homers.

A total of 131 players became free agents Thursday, and 53 more potentially are eligible pending decisions on team, player and mutual options during the next few days.

Among the pitchers available are major league ERA leader Hyun-Jin Ryu, Zack Wheeler, Madison Bumgarner, Rick Porcello, Cole Hamels, Jake Odorizzi and Dallas Keuchel, who went free after the 2018 season and waited until June to reach a one-year deal with Atlanta.

Others eligible include shortstop Didi Gregorius, third baseman Josh Donaldson and outfielders Yasiel Puig, Marcell Ozuna and Jose Abreu – the AL RBI leader.

Yankees closer Aroldis Chapman and Boston slugger J.D. Martinez also have the right to opt out, and catcher Yasmani Grandal has a mutual option with Milwaukee.

Teams must decide by Monday whether to make $17.8 million qualifying offers to their former players who became free agents, Players are eligible for the offer if they were on the roster for the season and never received a qualifying offer before. The price dropped for the first time, by $100,000, following a second straight slow offseason for roster moves.

RED SOX: New Red Sox chief baseball officer Chaim Bloom is filling out the team’s coaching staff, promoting Dave Bush to pitching coach and Kevin Walker as his assistant.

Bloom and Manager Alex Cora also named Peter Fatse as assistant hitting coach and hired Rey Fuentes as mental skills coordinator on Thursday.

Bush had been the Red Sox pitching coordinator last year after three seasons as a pitching development analyst. He pitched nine seasons in the majors, going 56-69 with a 4.73 ERA for Toronto, Milwaukee and Texas.

Walker spent time with the Padres, Giants and White Sox, going 7-3 with a 4.76 ERA over 122 games in six seasons. He has spent the last 11 years as a pitching coach in the Red Sox organization, most recently for Triple-A Pawtucket.

Fatse spent last season as the Twins’ minor league hitting coordinator. Fuentes was in the Cubs’ organization for the last seven years.

MARINERS:  The Seattle Mariners declined Wade LeBlanc’s $5.5 million option for the 2020 season, and the left-hander will become a free agent.

WHITE SOX-RANGERS: The Chicago White Sox traded catcher Welington Castillo to the Texas Rangers, who might not exercise an $8 million option for next season and allow him to become a free agent.

Texas also got an international signing bonus pool slot worth $250,000 in the deal while sending minor league infielder and outfielder Jonah McReynolds to the White Sox.

Castillo’s deal includes a $500,000 buyout for 2020. The 32-year-old catcher hit .209 over 72 games last season – his second with the White Sox and 10th in the majors.

YANKEES: The New York Yankees declined their 2020 option for Edwin Encarnacion, making the veteran slugger a free agent.

Encarnacion was due $25 million in 2020, but the Yankees bought out the remaining year of his contract for $5 million.

The Yankees acquired the three-time All-Star from Seattle in June to bolster a lineup sapped by injuries. Cash from the Mariners in the trade meant the deal cost New York just $8 million of what he was owed, including the buyout.

ROYALS: The Kansas City Royals hired Mike Matheny, bringing in a manager who took the cross-state Cardinals to the World Series six years ago before a three-season swoon cost him his job.

The 49-year-old Matheny went 591-474 with the Cardinals and was the first manager to reach the postseason his first four seasons. The Cardinals reached the World Series in 2013, losing to the Red Sox, but Matheny was fired in July 2018 with the team in jeopardy of missing the playoffs.

Matheny was hired last November by the Royals as a special adviser for player development, and the belief among many was that he was being groomed to take over when Ned Yost retired.

That happened shortly before the Royals finished another 100-loss campaign last month.

DIAMONDBACKS: The Arizona Diamondbacks declined the 2020 options for second baseman Wilmer Flores and left-handed pitcher T.J. McFarland.

Additionally, the Diamondbacks sent outfielder Abraham Almonte and left-handed pitcher Robby Scott outright to Triple-A Reno. They also announced infielder Kevin Cron had right knee surgery this month and is expected to be ready for spring training.

• The Diamondbacks added Matt Herges as their new pitching coach.

Herges, 49, replaces Mike Butcher, who was not retained after four seasons with the team.

Herges has been the San Francisco Giants’ bullpen coach for the past two seasons. He will be in charge of a promising D-backs pitching staff that includes Robbie Ray, Luke Weaver, Zac Gallen and Alex Young.

PHILLIES: The Philadelphia Phillies hired former Cincinnati Reds manager Bryan Price as their pitching coach.

Price joins new manager Joe Girardi’s staff after going 279-387 with Cincinnati over parts of five seasons from 2014-18. He previously was pitching coach for the Reds (2010-13), Diamondbacks (2006-09) and Mariners (2000-05).

ATHLETICS: Versatile reliever Yusmeiro Petit had his $5.5 million contract option for the 2020 season exercised by the Athletics.