He led the conference in numerous offensive categories, including batting average, slugging percentage and home runs, setting a new Rice freshman record.

However, in Rice's last game, in the Baton Rouge Super Regional, Rendon suffered an ankle injury that required surgery.

As a sophomore in 2010, he was the winner of the Dick Howser Trophy and was Baseball America's College Player of the Year, becoming the first underclassman in a decade to win the award.

After his Rice season ended, Rendon was invited to represent his country playing on the international circuit for Team USA.

[12] Days later, on June 15, Rendon clubbed his first major league home run off Vinnie Pestano of the Cleveland Indians.

[13] Rendon finished the season with the Nationals, putting up a .265/.329/.396 triple slash with seven home runs across 98 games with the major league club.

[14] After playing mostly second base the previous year, Rendon was moved back to his "natural position" as the Nationals' third baseman in the 2014 season.

Rendon placed fifth in National League Most Valuable Player voting and was awarded a Silver Slugger for his performance as a top-hitting third baseman.

[16] Rendon sprained the medial collateral ligament in his left knee early during spring training in 2015,[18] and then strained an oblique muscle while on a rehab assignment with the Class-AA Harrisburg Senators, being shut down on May 4.

[19] Rendon finally returned to major league action on June 4, 2015, but found himself moved back to second base, with the job of everyday third baseman being held down by new acquisition Yunel Escobar.

A sharp grounder off the bat of Brandon Crawford was deflected off the glove of first baseman Clint Robinson, caroming high into the air.

Playing deep on the infield shift, Rendon made a barehand grab on the deflected ball and fired to pitcher Felipe Rivero, who gloved it while diving across the first base bag to retire Crawford.

[23] On September 6, 2016, Rendon hit his first career grand slam off Williams Perez, which provided the Nationals with a winning margin of victory over the division rival Atlanta Braves in the 9–7 contest.

[26] He became the third player in major league history to attain both six hits and ten RBI in the same game, following Jim Bottomley (1924) and Walker Cooper (1949).

[27] Despite leading all National League position players in wins above replacement during the first half of the season, Rendon was not selected to participate in the All-Star Game.

[45] In a Covid-shortened 52 game season in 2020, Rendon batted .286/.418/.497 with 9 home runs and 31 RBIs, and tied for the AL lead by grounding into 10 double plays.

[50] On May 10, 2022, during Reid Detmers' no-hitter, Rendon hit his first left-handed home run, against position player pitcher Brett Phillips.

[56] Despite the original expectation that Rendon would be out for the remainder of the 2022 season, the Angels activated him from the injured list on September 28 and he began serving his suspension.

On April 3, 2023, Rendon was involved in a physical confrontation with a fan after the Angels' Opening Day game against the Oakland Athletics.

[59] In 2024, Rendon hit .267 in 19 games before suffering a left hamstring strain while attempting to beat out a ground ball on April 20, 2024.

[63] After returning to the Angels in early August, Rendon made yet another trip to the injured list with an oblique injury on September 10.

[65] On February 12, 2025, at the beginning of spring training, it was announced that Rendon would miss an extended period of time due to hip surgery.

[67][68][69] Explaining his philosophy on baseball to The Washington Post during spring training in 2017, Rendon said, "Obviously, I want to win, but at the same time, at the end of the day, it’s a game and that’s what I’m going to treat it as.

"[69] He claimed in a 2014 interview with the Post that he prefers watching the History channel to baseball, calling the sport "too long and boring".

[73] In the aftermath of Hurricane Harvey in August 2017, Rendon and then-Nationals teammate Matt Albers, a fellow Houstonian, set up a YouCaring fundraiser page to raise money for donations to the Houston Food Bank.