Ayr United made it a third consecutive win of the season to start the Scottish Championship with three points away to promoted Hamilton Academical.
Jay Henderson had gone close for the visitors before Oli Shaw missed from close range for Accies.
George Stanger fired the opener following an 18th-minute corner before Kevin O'Hara, Jamie Barjonas and Kyle MacDonald threatened for the hosts.
Shaw missed again from close range and Marco Rus had an effort denied before Accies' Scott Martin was sent off after 68 minutes for a second yellow card.
Four minutes later, Rus set up Anton Dowds to shape his shot beyond the goalkeeper to secure the victory.
MacDonald went close to pulling a goal back, while Jamie Murphy almost made the scoreline more comfortable.