The 14-year veteran joined the Lakers last August in a trade from the Washington Wizards. Westbrook averaged 22.2 points, 11.7 assists and 11.5 rebounds per game in 2020-21 for the Wizards.
He also averaged a triple double for his 2016-17 NBA MVP campaign and the 2017-18 and 2018-19 seasons, while with the Oklahoma City Thunder.
Westbrook's decision to opt into the final year of his contract comes a day after the Lakers were reported to have mutual interest in a potential acquisition for Brooklyn Nets guard Kyrie Irving. Irving then announced late Monday that he also plans to exercise his $36 million player option for 2022.
The NBA's contract option deadline is at 5 p.m. EDT Wednesday. The NBA's free agency period starts at 6 p.m. Thursday.