Early career McClelland started off playing football with
Shamrock Rovers at an early age. He moved on to Templeogue United and also enjoyed spells at
Peamount United &
Crumlin United before returning to
Shamrock Rovers where he played with their Under 19's side in the 2014–15 season. That proved to be his only senior appearance for Rovers as he moved on to
UCD in July 2015, playing for their Under 19's side.
UCD McClelland made his first senior appearance for
UCD on 19 July 2015 in a friendly against
Liverpool at the
UCD Bowl. With the UCD first team fatigued following their
UEFA Europa League campaign, it allowed McClelland a chance to make his first career senior appearance in a league game on 31 July 2015 when he came off the bench in a 3–0 win away to
Cabinteely. He was an unused substitute in 7 other first team games that season as he continued to play with the under 19's. The
2016 season was McClelland's first season as a full first team player. His first career goal came on 3 June 2016 when he scored a 64th-minute goal in a 2–0 win at home to
Shelbourne. He would again be the enemy of Shelbourne the following month when he scored an 84th-minute winner in a 2–1 win for UCD at
Tolka Park. His final goal of the season came on 30 September 2016 when he scored in an 8–1 demolition of
Waterford at the
RSC. He finished the season with 20 appearances and 3 goals. On 7 May 2018, he scored his first career hat-trick as his side thumped
Wexford 8–0 at
Ferrycarrig Park. On 28 September 2018, he played the full 90 minutes away to
League of Ireland Premier Division Champions Dundalk in the
FAI Cup Semi Finals as his side were denied a place in the
Aviva Stadium by a narrow 1–0 scoreline. That was the club's final game of the season in a year which saw McClelland score 10 goals in 32 appearances in all competitions and also receive the first silverware of his career as his side gained promotion by winning the
2018 League of Ireland First Division. 2019 saw McClelland's first taste of
League of Ireland Premier Division action. On 5 July he scored the winner in a crucial 1–0 victory over relegation fighting rivals
Finn Harps. The season proved to be a difficult one for UCD as they finished bottom of the league and were relegated back to the
First Division. The season did however provide a lot of experience at top tier level for McClelland, as he made 42 appearances in all competitions, scoring 4 goals. Upon signing, he spoke of his excitement at signing his first professional contract and his ambitions for the season ahead being to help the club get back to
UEFA Europa League qualification. He made his competitive debut on 14 February 2020, making the starting eleven as his side lost 1–0 against
Waterford in the opening game of the season at
Richmond Park. He played in 16 of the club's 19 league and cup games over the course of the shortened season due to the
Coronavirus pandemic, as his side missed out on European football on the final day of the season, finishing in 6th place. McClelland's first goal for the club came on 2 July 2021, scoring from 25 yards in a 3–2 loss to
Bohemians at
Dalymount Park with his side down to 9 men at the time. His first home goal at
Richmond Park for the club came in a 6–0 win over
Bray Wanderers in the
FAI Cup on 23 July 2021, scoring a diving header to give his side a 2-goal lead going into half-time. On 1 November 2021, McClelland scored his first home league goal for the club when he finished a
Jak Hickman cross from 5 yards to double his side's lead in the
Dublin City derby against
Bohemians on 1 November 2021. On 28 November 2021 McClelland scored his penalty in the
2021 FAI Cup Final penalty shootout, as his side defeated rivals
Bohemians 4–3 on penalties following a 1–1 draw after extra time in front of a record
FAI Cup Final crowd of 37,126 at the
Aviva Stadium. On 18 December 2021, McClelland signed a new contract with the club for the
2022 season. On 11 February 2022, he made came off the bench in the
2022 President of Ireland's Cup against
Shamrock Rovers at
Tallaght Stadium, as his side lost 5–4 on penalties after a 1–1 draw. On 18 February 2022, he scored his side's third goal in a 3–0 win away to
Shelbourne in the first league game of the season. On 12 November 2023, McClelland came off the bench in the
2023 FAI Cup Final, in a 3–1 win over
Bohemians in front of a record breaking
FAI Cup Final crowd of 43,881 at the
Aviva Stadium. On 27 November 2023, it was announced that McClelland has signed a contract extension with Pats, taking him into a 5th season with the club. On 11 August 2024, he scored his first goal of the
2024 season, opening the scoring in a 1–1 draw away to
Galway United with a 25-yard drive into the bottom right corner off the inside of the post. On 8 October 2024, McClelland was part of the Pats side that defeated
St Mochta's 2–1 in the final of the
2023–24 Leinster Senior Cup. On 4 December 2024, McClelland signed a new contract with the club, taking him into his 6th season there. McClelland scored his first goal of the
2025 season on 14 March 2025, scoring the final goal of the game in the 90th minute of a 3–0 win over
Bohemians at
Richmond Park, having replaced
Jake Mulraney from the bench 23 minutes earlier. On 7 August 2025, he provided the assist for
Simon Power's consolation goal in a defeat to
Turkish giants
Beşiktaş in the
UEFA Conference League. On 19 September 2025, McClelland scored the equaliser for his side in a 1–1 draw at home to
Galway United. On 8 December 2025, it was announced that McClelland had signed a new contract with Pats, taking him into his 7th season with the club. On 27 April 2026, he scored his first goal of the
2026 season, finding the bottom right corner from 30 yards in a 5–0 win over Blackrock College in the
Leinster Senior Cup. ==International career==