Early career A native of
Athboy,
County Meath, McGrath played youth football for his local club Athboy Celtic before joining top
Dublin youth side
Cherry Orchard. He played for
UCD under 19's before joining
St Patrick's Athletic under 19 side on their scholarship scheme with
NUI Maynooth. He played for Pats under 19's for two seasons, including a league winning campaign in which McGrath scored two goals against
Derry City under 19's in the final. He progressed into the first team in 2014 whilst still playing for the club's under 19 side.
St Patrick's Athletic 2014 season McGrath made his senior debut with the first team on 9 September 2014 as he played the full 90 minutes in a 2–1 win over
Longford Town in the
2014 Leinster Senior Cup Final at
City Calling Stadium. McGrath impressed Saints fans with his display, including an excellent through ball to set up Jack Bayly's winning goal in the 64th minute. His
League of Ireland debut came on 17 October 2014 when he started against
Athlone Town in a 2–0 loss at
Richmond Park.
2015 season He was named as a first team player ahead of the
2015 season, with number 19 being assigned to McGrath as his squad number. Mid season when first choice striker
Christy Fagan picked up a knee injury, McGrath had an extended run in the starting 11 as a striker and scored his first goals away to
Drogheda United and
Sligo Rovers in consecutive away games to secure 2–0 and 3–0 wins respectively. McGrath made his first appearances in
UEFA competition when he came on from the bench both away and at home against
Latvian side
Skonto Riga in the
Europa League. McGrath came on at the start of extra time in the
2015 League of Ireland Cup Final as Pats drew 0–0 with
Galway United before winning 4–3 on penalties to win the League Cup at
Eamonn Deacy Park. McGrath received rave reviews from fans, pundits and the media alike for his breakthrough season, coming in a second behind
Lee Desmond in the club's Young Player of the Year awards.
2016 season Although he struggled with shin splints that kept him out of games at the beginning of the
2016 season, his importance to the team increased in a season where the team struggled to deal with the midfield losses of
Chris Forrester,
Greg Bolger,
Killian Brennan and
James Chambers. Those losses however, created an opportunity for McGrath to play a lot of games in the role of attacking midfielder throughout the season. His first goal of the season was an 89th-minute strike to rescue a point at home to relegation fighting
Longford Town live on
Eir Sport. His only appearance in Europe for the season came against
Dinamo Minsk of Belarus as Pats lost 1–0 at home and were knocked out of the
Europa League in the second qualifying round. McGrath played a huge part in the Saints retaining their League Cup trophy as he played in every game, scoring away from home against
Bray Wanderers in the quarter-finals,
Shamrock Rovers in the semi's and
Limerick in the Final. Following a good season for McGrath, he was voted
St Patrick's Athletic Young Player of the Season by the club's supporters.
Dundalk McGrath moved from
St Patrick's Athletic to
Dundalk for an undisclosed transfer fee on 15 January 2017.
St Mirren After winning back-to-back
League of Ireland Premier Division titles with Dundalk, McGrath signed a -year deal with
Scottish Premiership side
St Mirren on 7 January 2020. He was named as the club's Player of the Year for the
2020–21 season by the club's supporters after scoring and impressive 17 goals in 45 appearances in all competitions from midfield.
Wigan Athletic On 31 January 2022, transfer deadline day, McGrath signed for
EFL League One club
Wigan Athletic on a two-and-a-half-year contract. After making four appearances for the club, he spent the 2022–23 season on loan at
Dundee United, before on 26 July 2023, making the decision to terminate his contract due to repeated contractual breaches by the previous owners of Wigan, despite the club's efforts to retain him.
Dundee United loan On 3 August 2022, he joined Dundee United on loan until the end of the 2022–23 season. He made his debut the following day, providing the assist for
Glenn Middleton's goal in a 1–0 win over
AZ Alkmaar in the
UEFA Europa Conference League. McGrath made 32 appearances in all competitions over the course of the season, scoring 7 goals, but this was not enough to help his side avoid relegation to the
Scottish Championship as they finished bottom of the table.
Aberdeen After leaving Wigan, McGrath returned to the
Scottish Premiership by signing a two-year contract with
Aberdeen on 22 August 2023. He made his debut two days later, coming off the bench in the 70th minute away to
BK Häcken in the
UEFA Europa League, helping his side to comeback from two goals down to earn a 2–2 draw. On 30 September 2023, McGrath scored in a 3–1 win over
Rangers at
Ibrox Stadium on his 27th birthday. On 9 November 2023, he scored his first career European goal when he found the bottom corner with a 30 yard free kick away to
PAOK to level the scores at 2–2 in his sides
UEFA Europa Conference League draw at the
Toumba Stadium. In January 2025, he sustained a shoulder injury that required surgery, with the intensive rehabilitation period keeping him out of action for several months. McGrath signed a pre-contract agreement with
Hibernian in February 2025.
Hibernian McGrath joined
Hibernian in June 2025, having agreed a four-year contract with the club earlier that year. On July 24, he scored within seven minutes of his debut against Danish side
FC Midtjylland in the first leg of the second round of the
2025–26 UEFA Europa League qualifying. ==International career==