He has some Thelonious Monk influences, especially in his phrasing, but Roberts' models have predominantly been Jelly Roll Morton and Fats Waller. While his earliest work reflected pronounced gospel and blues ties mixed with bebop, Roberts later devoted himself to stride and ragtime.

Roberts studied piano at Florida State University after beginning on the instrument in his youth. He won several competitions in the mid-'80s, then joined Wynton Marsalis' band as his first regular pianist after Kenny Kirkland. Roberts emerged as the Marsalis band's second prime soloist, and the hub of its rhythm section. His swing kept the group focused, and prevented Marsalis' music from getting too stiff or introspective. Roberts' own late-'80s and '90s albums for RCA/Novus, particularly the 1990 release Alone with Three Giants, detailed his commitment to classic music.

He continued to explore the past even upon the arrival of the 21st century with such albums as 2001's Cole After Midnight (a concept album featuring interpretations of Nat King Cole and Cole Porter) and 2009's New Orleans Meets Harlem, Vol. 1 (another trio date, this time focusing on the music of Duke Ellington and Scott Joplin as well as Monk, Morton, and Waller), his first album as a leader in eight years. The holiday-themed Celebrating Christmas followed in 2011. ~ Ron Wynn