Brathwaite made his first-class debut aged just 16 and impressed, scoring 73 while opening the batting for Barbados. He was called up for the West Indies squad for the Test series against Bangladesh in 2009, when senior players had gone on strike, and was subsequently awarded a contract by the West Indies Cricket Board.

A patient batsman, who likens his batting style to Shivnarine Chanderpaul, Brathwaite won a place in the West Indies Under-19 squad for the World Cup in 2010 in New Zealand. He was West Indies' leading run-scorer and overall second highest with 335 runs with four fifties.