Minor and under-21 Hayes first played for
Limerick when he was added to the minor panel shortly before the start of the
2015 Munster Minor Championship. He made his first appearance for the team on 8 April 2015 when he lined out at midfield in a ten-point defeat by
Cork in the
Munster quarter-final. Switched to the half-forward line as Limerick regrouped during the rest of the provincial campaign, Hayes was at right wing-forward when Limerick were beaten by three points by
Tipperary in the
Munster final. Eligible for the minor grade again the following year, he was selected at centre-forward when Limerick suffered a second successive defeat by Tipperary in the
2016 Munster final. On 4 September 2016, Hayes scored a point from full-forward when Limerick were beaten by 1-21 to 0-17 by Tipperary in the
All-Ireland final. After the end of his minor career, Hayes was immediately added to the Limerick under-21 panel for the
2017 Munster Under-21 Championship. After making his first appearance for the team in an 11-point
quarter-final defeat of Tipperary, he ended the championship with a
winners' medal after Limerick's 0-16 to 1-11 defeat of Cork in the final. On 9 September 2017, Hayes lined out at centre-back in Limerick's 0-17 to 0-11 defeat of
Kilkenny in the
All-Ireland final. He ended the season by being named in the centre-back position on the Team of the Year. Hayes was again eligible for the under-21 team in
2018 and was also appointed team captain. He made his last under-21 appearance on 21 June 2018 in a
Munster semi-final defeat by Tipperary.
Senior 2017 season Hayes was still just 18-years-old and out of the minor grade when he was drafted onto the senior panel by new manager
John Kiely in advance of the
2017 Munster League. He made his first appearance of the pre-season competition on 8 January 2017, when he came on as a half-time-minute substitute for right corner-back
Seánie O'Brien in a
first-round defeat of
Waterford. Hayes received his first competitive start on 22 January 2017 when he lined out at right wing-forward in a 24-point
fourth-round defeat of
Kerry. He was retained on the panel for the
2017 National League campaign, making six appearances, including at full-forward in Limerick's ten-point defeat by
Galway in the
semi-final. Once again making the cut for Limerick's
2017 Munster Championship panel, Hayes made his championship debut on 4 June 2017 when he scored 1-01 from play in a 3-17 to 2-16 defeat by
Clare in the
Munster semi-final.
2018 season In November 2017, Hayes was again named on the 38-man Limerick panel for the upcoming
2018 season. After playing no part in Limerick's successful
Munster League campaign, he made a number of appearances throughout the subsequent
National League, including at centre-forward in a second successive
semi-final defeat. Hayes established himself as Limerick's first-choice centre-forward throughout the championship and was selected in that position when Limerick faced
Galway in the
2018 All-Ireland final. He scored four points from play as Limerick won their first
All-Ireland Championship title in 45 years after a 3-16 to 2-18 win. Hayes was also selected as the official
man of the match. He ended the season by being nominated for an
All-Star Award, while he was also named
Young Hurler of the Year.
2019 season Hayes was again a regular for Limerick during the
2019 National League, making five appearances during their eight games. He was held scoreless from centre-forward when Limerick claimed their first
Division 1 title since
1997 after a 1-24 to 0-19 win over
Waterford in the
final. Hayes ended the
2019 Munster Championship with his first
provincial winners' medal after scoring 1-02 from play in the 2-26 to 2-14 win over
Tipperary in the
Munster final. He again received an All-Star nomination at the end of the season, while he was also shortlisted for a second successive
Young Hurler of the Year award but lost out to
Kilkenny's
Adrian Mullen.
2020 season Commitments with the
University of Limerick for the
2020 Fitzgibbon Cup campaign precluded him from lining out with Limerick during their title-winning
Munster League campaign. The subsequent
National League campaign saw Hayes line out in three of Limerick's five
Division 1A games. On 25 October 2020, he was again at centre-forward in a 0-36 to 1-23 defeat of
Clare in the
delayed league final. For the
Munster semi-final against
Tipperary on 1 November 2020, he was surprisingly switched from the forwards to defence, lining out at left wing-back with
Cian Lynch taking over the centre-forward position. Hayes ended the
2020 Munster Championship with a second successive winners' medal after again playing at left wing-back in the
Munster final defeat of
Waterford. On 13 December 2020, he scored a point from his now customary position of left wing-back when Limerick defeated Waterford by 0-30 to 0-19 in the
All-Ireland final. ==Personal life==