He made his competitive debut for Bohemians in a FAI League Cup tie against St Patrick's Athletic on 26 August 1979, which they lost on penalties.
Ten days later he made his European debut at the Estádio José Alvalade against Sporting Clube de Portugal in the UEFA Cup.
He later played for Sligo Rovers, Crusaders (with whom he won the County Antrim Shield and was leading scorer in his first season), Glentoran, Bangor, Coleraine,[6] Cliftonville, Larne and Home Farm.
Bohemians were a side which, despite being tipped as outside contenders for the title at the start of the year, were facing a relegation dogfight when Collins arrived in the 1998–99 season.
Collins' start to his reign as Bohs' manager was relatively impressive, and new signings such as Kevin Hunt eventually dragged the side out of relegation trouble and to safety.
However, a poor run of results at the end of the season saw the Gypsies, which has never been outside of the top tier of Irish football, plummet back into relegation trouble, and were forced to take part in a play-off with Cobh Ramblers.
During the close-season Collins oversaw a massive change in personnel at the club, with old stalwarts such as Brian Mooney, Tommy Byrne (footballer) and Peter Hanrahan being released, and new signings such as Glen Crowe, Mark Dempsey, Wayne Russell and Avery John coming in.
Collins again brought in several new players during the summer break, with Simon Webb, Dave Hill among others joining record signing Trevor Molloy at the club.
Bohemians' opening game was an away tie in the UEFA Cup against Aberdeen FC, which was to be the first time that the club had fielded a starting eleven consisting entirely of full-time professional players.
Bohemians were reduced to 10 men after 45 minutes and were beaten 1–0 in the return leg, due to an own-goal, but progressed on the away goals rule and faced German giants Kaiserslautern in the next round[10][11] Despite putting in an impressive display, Bohemians who were again reduced to 10 men on the 43rd minute were beaten 3–1 in Tolka Park in the first leg, and suffered from some careless defensive lapses and a controversial red card.
It was at this time in his career that Collins is rumoured to have applied for a job with Dublin Corporation as a traffic warden to escape the hectic lifestyle of football.
[citation needed] In the league that season Bohs were showing good form, though with Glen Crowe emerging as a phenomenal goal-scorer and Kevin Hunt marshalling the midfield.
Shelbourne were clear leaders at the top, and a huge investment in the Bohemians playing side looked set to fail to reap just rewards.
That result, coupled with a break for several weeks due to the foot and mouth outbreak in the UK and Ireland, gave Bohemians the momentum to mount a late challenge for the league.
The following weekend Bohemians beat Longford Town in the FAI Cup Final thus securing their first double in 75 years, a remarkable achievement.
To the present day Collins' name is sure to spark intense debate amongst the Bohemians faithful, with some fans opposing and supporting the former manager.
[14] A club that was under financial embargo with only 8 senior professional players and bookies favourites for relegation, was 14th in the league by April their highest position in 5 seasons.
[15] Collins was sacked in April 2002 after stating that he would resign unless owner Michael Knighton completed the sale of the club as promised to the investor John Courtenay (chairman).
Due to the long drawn out completion of the sale Collins worked with a weakened squad but yet again he retained their League status and took them to Cardiff's Millennium Stadium for the LDV Cup Final.
[21] He later brought a claim of unfair dismissal against Shamrock Rovers to the Employment Appeals Tribunal in Dublin, the case was settled out of court in November 2006.
The fans appreciated his honesty and applauded in agreement when he told them that "we are embarking on a long term project, all of us will stand together and make this club greater still!"
His son Roddy Collins Jr. was a League of Ireland footballer who played for Athlone Town, Derry City and Waterford United.