On 11 March 2010, Downes scored 1-02 from play when Ardscoil Rís defeated Thurles CBS in the final of the Harty Cup.
On 2 October 2011, Downes scored 1-01 from full-forward in Na Piarsaigh's 2-18 to 0-13 defeat of Adare to win their very first Limerick Championship title.
[5] After surrendering their titles the following year, Downes won a second Limerick Championship medal after lining out at centre-forward when Na Piarsaigh defeated Adare by 0-14 to 0-12 on 6 October 2013.
[6] He was retained at centre-forward for the subsequent Munster Championship, which culminated on 24 November 2014 with him winning a second provincial medal after scoring a goal in the 4-14 to 0-08 defeat of Sixmilebridge in the final.
[8] Downes missed Na Piarsaigh's subsequent Munster Championship final defeat of Ballygunner due to a concussion.
[9] On 17 March 2016, he won an All-Ireland Championship medal after scoring 1-02 in Na Piarsaigh's 2-25 to 2-14 defeat of Ruairí Óg in the final.
[10] On 15 October 2017, Downes won a fourth Limerick Championship medal when Na Piarsaigh defeated Kilmallock by 1-22 to 2-14 in the final.
[12] On 17 March 2018, Downes was named at full-forward by played much of the match at left corner-forward when Na Piarsaigh suffered a 2-17 to 1-17 defeat by Cuala in the All-Ireland final.
He started the game on the bench but was introduced as a 65th-minute substitute and scored two points in Limerick's 0-24 to 0-15 defeat of Cork and a first title in 17 years.