Arenado will need to formally waive his no-trade clause before the trade can be finalized, and his opt-out clause after the 2021 season must be addressed. MLB and the players' union also must approve the agreement.
The 29-year-old Arenado is scheduled to earn $35 million in 2021 as part of an eight-year, $260 million contract he signed with the Rockies in 2019. The deal includes an opt-out clause after the 2021 campaign.
If the deal between the Rockies and Cardinals is finalized, Arenado will keep his opt out after 2021, according to The Athletic. He also will get an additional opt out after 2022 and retain his full no-trade clause.
Arenado, a five-time All-Star selection, had a .253 batting average with eight home runs and 26 RBIs in the pandemic-shortened 2020 season. He also earned an eighth straight Gold Glove Award.
In the 2019 campaign, Arenado hit a career-best .315 with 41 home runs and 118 RBIs.
Since making his major league debut in 2013, Arenado has recorded a .293 average with 235 home runs and 760 RBIs in 1,079 career games with the Rockies.