Holland made his Munster A debut on 19 November 2011, coming on as a substitute against Neath.[2] He made his senior debut for Munster on 23 November 2013, coming on as a substitute against Cardiff Blues.[3] Holland was awarded a development contract with the senior Munster squad for the 2014–15 season in March 2014.[4] Holland was nominated for the John McCarthy Award for Munster Academy Player of the Year on 1 May 2014.[5]
Holland made his first start for Munster on 19 September 2014, against Zebre in the Pro12.[6] He signed a two-year contract with Munster in January 2015, advancing from a development contract to a full contract.[7]
On 25 March 2016, Holland started against Zebre in a 2015–16 Pro12 game, scoring 10 points.[8] On 2 April 2016, Holland started against Leinster, scoring all of Munster's points, including a try, in Munster's 16–13 defeat.[9] On 1 September 2016, it was announced that Holland had been forced to retire from rugby with immediate effect after being advised to do so on medical grounds, having suffered a recurrence of a hamstring injury first sustained in November 2014.[10]