Colleges Smyth first experienced success on the hurling field during his tenure at
St. Flannan's College, a famed hurling nursery in
Ennis. At Flan nan's he was a hurling protégé, going straight into the
Dean Ryan Cup team as a thirteen-year-old and winning his first medal when Ennis won the junior championship. In his second year he made his debut on the
Harty Cup team. He won his first Harty Cup medal that year as St. Flannan's defeated
the North Monastery of
Cork to take the title. The subsequent All-Ireland final saw Smyth's side face St Joseph's of Marino. A 7–10 to 2–3 trouncing gave Smyth his first
All-Ireland medal. St Flannan's retained their Harty Cup crown in 1946 following another defeat of the North Mon. O'Connell School from
Dublin were the opponents in the All-Ireland final and a close game developed. A 5–7 to 5–2 scoreline gave Smyth his second All-Ireland medal. Smyth collected a third consecutive Harty Cup medal following a defeat of
St. Colman's College in 1947. Once again St Flannan's reached the All-Ireland decider where St Joseph's of
Roscrea provided the opposition. A 6–8 to 3–1 victory gave Smyth a third consecutive All-Ireland medal. At St Flannan's Smyth also won three inter-provincial colleges medals with the Munster selection.
Club Smyth played his club hurling with
Ruan and enjoyed much success. In 1948 Smyth represented Ruan in the minor, junior, intermediate and senior grades. It was a successful year as Ruan defeated
Clarecastle in the county decider, giving Smyth his first
championship medal. He also collected an intermediate championship medal that same year. Having secured their very first championship title, Ruan captured a second three years later in 1951. After a period in the doldrums, Smyth's side reached the championship decider once again in 1959. A defeat of
Éire Óg gave Smyth his third championship medal. A defeat of
Scariff in the final of 1960 gave Ruan a famous two-in-a-row. It was Smyth's fourth championship medal. Three-in-a-row proved beyond Ruan, however, the team reached the final once again in 1962.
Sixmilebridge fell on that occasion, giving Smyth a fifth and final championship medal.
Inter-county Smyth first came to prominence on the inter-county scene as a member of the
Clare minor hurling team. He made his debut as a fourteen-year-old in 1945 and subsequently set up what must be an all-time record for Clare by playing at this grade for five years in a row. In his debut year, Clare reached the
Munster decider. An 8–10 to 0–2 trouncing by
Tipperary was Clare's lot on that occasion. As a seventeen-year-old Smyth made his senior debut in a
National Hurling League game against
Galway in 1948. He played no part in the subsequent 1949 championship due to his involvement as captain of the Clare junior hurling team. He won a
Munster medal in that grade following a 3–3 to 0–6 defeat of
Cork. Clare later defeated
Kilkenny before facing
London in the All-Ireland decider. A close game developed and, at the full-time whistle, Clare were narrowly defeated by 3–7 to 3–6. Smyth made his senior championship debut in a Munster semi-final defeat by
Tipperary in 1950. Within just a few seasons he became known as one of the most prolific scorers in the championship. His 6–4 against
Limerick in the Munster quarter-final in 1953 is a record which still stands. In 1954 Clare qualified for the final of the post-season
Oireachtas Tournament. All-Ireland runners-up
Wexford provided the opposition on that occasion, however, the game ended in a 2–8 apiece draw. The replay was also a close affair with Clare eventually triumphing by 3–6 to 0–12. It was Smyth's first silverware with the Clare senior hurling team. The following year Smyth's side dominated the provincial championship. Defeats of Cork and Tipperary led to Clare being installed as the favourites to take the Munster crown for the first time since 1932.
Limerick provided the opposition and went on to defeat an optimistic Clare side by 2–15 to 2–6. Smyth added a
Thomond Feis medal to his collection in 1956 as Clare won the pre-season warm-up tournament. In late 1964 Smyth dropped out of the Clare team. This was surprising as he was just as prolific as ever, scoring 16–27 for Clare in seven outings in 1963. His retirement from the inter-county scene at this stage was premature but he returned to play for the Clare intermediate team in 1966 before making a return to the Clare senior team in 1967. That year he lined out in his second-ever Munster decider. A 4–12 to 2–6 defeat by Tipperary brought the curtain down on Smyth's inter-county career.
Inter-provincial Smyth also had the honour of lining out with
Munster in the inter-provincial series of games. He first lined out for the team in 1952 and was an unused substitute as Munster claimed the
Railway Cup that year. By 1955 Smyth had made his way onto the starting fifteen. He won his first Railway Cup medal on the field of play that year as Munster defeated
Connacht by 6–8 to 3–4. After surrendering their title in 1956, Munster bounced back the following year with Smyth lining out in the forwards. A 5–7 to 2–5 defeat of
Leinster gave him his second Railway Cup medal. It was the first of five successive Railway Cup titles for Munster with Smyth playing a prominent role in all of those successes. Six-in-a-row proved beyond Munster, however, the province reached the Railway Cup decider again in 1963. A narrow 2–8 to 2–7 defeat of Leinster in a replay gave Smyth his seventh Railway Cup medal on the field of play and an eight overall. It was also his last appearance for Munster. ==Personal life==