In 2016, Rivera played for the rookie-level Burlington Royals, posting a .249/.317/.373 slash line in 58 games. The following year, he played for the Single-A Lexington Legends, slashing .310/.364/.468 with 12 home runs and 72 RBI. In 2018, Rivera split the season between the High-A Wilmington Blue Rocks and the AZL Royals, batting a cumulative .274/.326/.416 with 6 home runs and 63 RBI. For the 2019 season, Rivera played for the Double-A Northwest Arkansas Naturals, logging a .258/.297/.345 slash line with 7 home runs and 57 RBI in 131 games.[2]
Rivera did not play in a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.[3] He was assigned to the Triple-A Omaha Storm Chasers to begin the 2021 season, and batted .282/.337/.593 with a career-high 14 home runs and 40 RBI in 44 games.
On June 28, 2021, Rivera was selected to the 40-man roster and promoted to the major leagues for the first time.[4] He made his MLB debut that day as the starting third baseman against the Boston Red Sox, and logged his first career hit in the game as well, a single off of Sox starter Garrett Richards. He was placed on the injured list on June 30 with a left hamate break.[5] He finished his rookie season appearing in 29 games for the Royals and hitting .256/.316/.333 with one home run, 5 RBI, and 2 stolen bases. In 2022, Rivera made 63 appearances for Kansas City, slashing .237/.284/.399 with 6 home runs and 22 RBI.
Arizona Diamondbacks
On August 1, 2022, the Royals traded Rivera to the Arizona Diamondbacks for pitcher Luke Weaver.[6] He played in 39 games for the Diamondbacks down the stretch, hitting .227/.304/.424 with 6 home runs and 18 RBI.
Rivera was optioned to the Triple-A Reno Aces to begin the 2023 season.[7] In 86 games for the Diamondbacks, he batted .261/.314/.358 with four home runs and 29 RBI. On March 28, 2024, Rivera was designated for assignment after failing to make Arizona's Opening Day roster.[8]
Miami Marlins
On April 2, 2024, Rivera was traded to the Miami Marlins in exchange for cash considerations.[9] In 96 games for Miami, he slashed .214/.294/.269 with one home run and 15 RBI. Rivera was designated for assignment by the Marlins on August 19.[10]
Baltimore Orioles
On August 21, 2024, Rivera was claimed off waivers by the Baltimore Orioles.[11] He had a pair of home runs and career highs with four hits, four RBI and eleven total bases in a 9–2 away victory over the Minnesota Twins in the penultimate game of the regular season on September 28.[12]