Ross Callachan's penalty enabled Hamilton to beat Kilmarnock and move off the bottom of the Premiership table.
Kilmarnock were reduced to 10 men after just 29 minutes when Clevid Dikamona was dismissed.
But the visitors defended resiliently until referee Willie Collum awarded the hosts a penalty on 73 minutes.
It came in controversial fashion when Collum adjudged that Callachan's shot struck Brandon Haunstrup on the arm to leave Kilmarnock furious.
The decision appeared harsh but Callachan remained unfazed, despite his penalty miss at Tannadice a few weeks ago, and slotted the penalty past Danny Rodgers.
Kilmarnock were incensed by the decision's and will be frustrated to have lost after performing valiantly following Dikamona's dismissal, their fifth red card of the season.
The former Hearts defender crazily dived in two-footed on Scott Martin and although he won the ball, Dikamona was reckless and referee Column showed no hesitation to brandish a red card.
Hamilton made an encouraging start and after a misjudgment from Dikamona, Callum Smith attempted to lob Danny Rodgers but the ball flew over the bar.
Kilmarnock possessed a real threat all afternoon through the pairing of Eamonn Brophy and Nicke Kabamba.
Brophy constantly threatened in behind and he should have done better on 14 minutes when he beat the offside trap but fired high and wide.
Kilmarnock had the better opportunities in the first-half and Ben Stirling had to make an excellent block to deny Brophy on 23 minutes.
Nathan Thomas was brought on by Brian Rice in an attempt to add an attacking impetus to Hamilton and the substitute almost made an immediate impact. The 26 year-old collected possession on the right before cutting in and unleashing a powerful left-footed shot that Rodgers palmed clear.
Alex Dyer was forced to move Mitch Pinnock to left-back after Dikamona's dismissal and Thomas caused him all sorts of problems. He burst past the makeshift defender on 68 minutes before cutting the ball back to the edge of the area but Scott Martin fired wildly over the bar.
Hamilton almost secured the three points on 84 minutes when Tunde Owaolabi showed brilliant pace to race clear but he fired into the side netting from a tight angle.
Kilmarnock pressed forward for an equaliser in the closing stages and Brophy headed Kirk Broadfoot's cross narrowly wide. The visitors tried everything to grab a late equaliser but Hamilton held on for a crucial three points.