In 2010, Keenan became a graduate of The Juilliard School and is currently completing his Masters degree at Westminster Choir College.

Keenan is known for virtuosic pipe organ performances that display a "clear technique" and "comprehensive, symphonic use" of the organ. As a student of Ken Cowan in 2011, Keenan studied and performed Mr. Cowan's arrangement of Franz Liszt's "Mephisto Waltz No. 1." In the upcoming year, Keenan will study with Alan Morrison. While pursuing undergraduate work at The Juilliard School, Keenan won first prize in Region IX of the American Guild of Organist's Regional Young Organist Competition and was featured in concert at the 2008 AGO Regional and National Conventions. Keenan has performed at well-established organ concert venues such as Saint Mary-The-Virgin and Saint Ignatius Loyola of New York City and was featured on the 2010 Rising Stars summer concert series at Spreckels Organ Pavilion in Balboa Park, San Diego, CA. Most recently, Keenan gave his solo organ debut recital at Bryn Mawr Presbyterian Church, where he is Assistant Organist.

Keenan shares his love for collaboration by working with singers and instrumentalists of both contemporary and classical genre. His work with soprano, Barbara Paterson, led to their participation in the 2011 Nadia and Lili Boulanger International Voice-Piano Competition in Paris, France with coaching from Dalton Baldwin and Mary Anthony Cox. Keenan coaches regularly with Susan Ashbaker and accompanies for students of Westminster Choir College. In 2011 and 2012, Keenan was a collaborative pianist for Westminster's CoOPERAtive Program, working with Kathleen Kelly of Vienna State Opera, Gina Lapinski of NY Metropolitan Opera and Sandra Bernhard of Houston Grand Opera. His upcoming season will feature collaborations with Opera Company Philadelphia, Singing City, Lyric Fest, Lyric Fest's Co-Founder Suzanne DuPlantis and Westminster Choir College Opera Theatre.

Keenan's passion for contemporary music drives him to produce recitals that feature musical peers in collaboration with him on organ. In 2010, Keenan's collaborative recital at The Juilliard School saw the debut of a work encompassing dance, drums, guitar and organ. Contemporary organ works were arranged to convey a story visually expressed by nearly half the freshman class of Juilliard dancers. In January 2012, Keenan debuted a new work for voice, drums, mandolin, electronics and organ as a featured artist at Old First Church in San Francisco, CA. This work featured organ arrangements of music by Kanye West and the Fleet Foxes.