As Nabucco:

“Mark Rucker offered a commanding portrayal of the title role. This Nabucco battled Hebrews and hubris in dramatically persuasive fashion, all the while pouring out a golden tone that maintained its evenness from top to bottom. The baritone's incisive way of shaping a phrase reached a peak of Verdian richness in "Dio di Giuda".” - Opera News

“The title role went to Mark Rucker, the American singer who has made a specialty of the twisted, conflicted roles that Verdi created for baritones. Rucker’s voice is an instrument of great tonal beauty, but he didn’t just upholster every aria with vocal velvet. He brought out the king’s desperate humanity, with touches of rawness and vulnerability, as he pleaded for his daughter’s life and as he lamented his fallen state in Oh di qual onta aggravasi questo mio crin canuto". - South Florida Classical Review

“Each principal in PBO’s Nabucco offered a performance of individual value, with the balance of the night’s success tipping aptly on Mark Rucker’s Nabucco. Rucker presented fluent Verdi style, adding — of late — further finesse to a cantabile line that already made him a notable exponent of the style and period. The power-addled king’s delusions of Acts II and III were conveyed in Rucker’s singing — fashioned with portamento and diminuendos; he hit his stride vocally and dramatically with a ‘Dio di Giuda’ both meditative and conciliatory." - OperaNews