[2] He made his One Day International debut for the West Indies against Sri Lanka on 4 November 2015.

Blackwood then steered his team to victory in the third Test at Barbados hitting 53 not out with the winning runs coming off the bowling of Moeen Ali.

In September 2019, in the second innings of the second Test against India, Blackwood replaced Darren Bravo as a concussion substitute in the West Indies' squad.

[6] In March 2020, in round eight of the 2019–20 West Indies Championship, Blackwood scored his maiden double century in first-class cricket, with 248 runs against the Leeward Islands.

[9] The Test series was originally scheduled to start in May 2020, but was moved back to July 2020 due to the COVID-19 pandemic.