Career
He normally plays as a Fly-half, but has occasionally played as a Centre. He made his debut for against Connacht on 18 April 2010, starting at fly-half. On 5 May 2012, Cusack came off the bench for in the last league fixture of the 2011-2012 season against Ulster and scored his first points for the province, a conversion of "s fourth try.
lieutenant was announced on 3 May 2012 that Cusack will be leaving at the end of the 2011-2012 season.
He recently signed a short-term contract with RFU Championship side until the end of the 2012-2013 season. He also joined the Plymouth squad for the 2013-2014 season.
Cusack joined another RFU Championship side,, at the beginning of the 2015-2016 season.