Kilmarnock secured a narrow victory over fellow Scottish Premiership team Livingston, taking control of Premier Sports Cup Group H at Rugby Park.
Livingston nearly took the lead when Stevie May broke through on goal, but the experienced forward was thwarted by Kilmarnock's goalkeeper, Max Stryjek.
However, it was Kilmarnock who went ahead in the 31st minute when a misjudged punch by Livingston goalkeeper Jerome Prior deflected off teammate Mo Sylla and into the net.
Although Livingston dominated possession and created numerous chances after falling behind, they could not overcome Stryjek's defense on a frustrating evening.
David Martindale's team lost momentum in the final stages, and Kilmarnock missed opportunities to extend their lead, with Marley Watkins' shot being saved by Prior and Bruce Anderson heading wide.
Kilmarnock tops the group with maximum points from their two matches, while Livingston has three points from their two games.
Stuart Kettlewell's squad will host Kelty Hearts on Tuesday, while Livingston's next match is against Brora Rangers on Saturday.