Grant told Boro's Assistant Manager, Harold Shepherdson, that Cummins had the keenest football brain he had encountered in a boy, and was the most naturally-talented player he had seen since Hughie Gallacher.
Shepherdson signed Cummins on Associate Schoolboy Forms for Middlesbrough at age 14, staving off competition from Chelsea, Arsenal, and Aston Villa, to name a few clubs wanting his signature.
Manager Jim Morrow decided that Cummins was too small, and would not have the stamina to compete against the German Schoolboys' under-15 team at Wembley Stadium.
Cummins began his career with Middlesbrough in 1975 as an apprentice professional, and was coached at youth level by George Wardle, and then by former Scotland and Celtic great Bobby Murdoch.
Manager Jack Charlton gave him his debut in the old First Division (now the Premier League) against Ipswich Town at Ayresome Park on 27 November 1976 at the age of only 17, and Cummins went on to become a firm crowd favourite.
In 1977, Cummins had the honour of playing with 1966 World Cup Winner Sir Bobby Charlton in John Hickton's Testimonial Match against Sunderland, at Ayresome Park.
In the summer of 1977, he played in the North American Soccer League (NASL) at the age of 18 for the Minnesota Kicks against the likes of Pelé, Franz Beckenbauer, Giorgio Chinaglia, and his idol George Best, winning the Western Division Championship.
In the summer of 1981, he returned to the NASL and played for the Seattle Sounders alongside Bruce Rioch and Alan Hudson, winning the Trans-Atlantic Challenge Cup against the New York Cosmos, Glasgow Celtic and Southampton.
In May 1985, he captained Sunderland to victory over Middlesbrough in the Final of the Bradford City Disaster Fund North East of England Six-a-Side Tournament held at Teesside Park.
[1] He left the club following relegation in 1985 for the US at the age of 26 and joined the Minnesota Strikers on a three-year contract in the Major Indoor Soccer League (MISL).
However, they were crowned MISL Eastern Division Champions in 1988 and on 8 April Cummins scored a hat-trick in the Strikers 4–2 victory against the Chicago Sting and he was carried shoulder high from the playing field by his teammates at the end of the game.