HATTIESBURG, Miss. (AP) - Rakeem Cato threw for 340 yards and three touchdowns and Kevin Grooms added a pair of scores on the ground as Marshall eased past winless Southern Mississippi 59-24 Saturday night.

Cato completed 22 of 31 first-half attempts as the Thundering Herd (3-4, 2-1 Conference USA) built a 31-17 halftime lead on 374 yards of total offense.

The first passing touchdown came early in the second quarter. Cato connected with Antavious Wilson on a wide receiver screen for a 14-yard touchdown, giving Marshall a 17-3 lead.

Southern Mississippi (0-7, 0-3) responded with Kalan Reed's 19-yard interception return for a score, but Grooms answered three plays later with a 64-yard TD to put the Thundering Herd up 24-10.

Cato connected with Tommy Shuler for touchdown passes on consecutive possessions in the second half, and Grooms scored from 11 yards out, extending Marshall's lead to 45-17 at the end of the third quarter.