Marshall's initial senior appearance was a Geddes Grant/Harrison Line Trophy (List A) match for Barbados on 13 February 1978; again he got out without scoring and did not take a wicket. Four days later, he made his first-class debut against Jamaica, and whilst he failed to score runs, he claimed 6–77 in the Jamaican first innings. On the back of this single first-class appearance he was selected to tour India in 1978/79, many first-choice West Indian stars being unavailable having committed themselves to playing World Series Cricket. Marshall heard of his selection on the radio while working in the storeroom at Banks Brewery and later claimed he did not know where India was.