Bradley was first called up to the Derry Senior panel in 2004 by Mickey Moran.
He made his debut in the Dr. McKenna Cup against Antrim, but suffered a horrific leg break against Jordanstown in the next outing and was out for a year and a half.

Bradley and Derry reached the Dr. McKenna Cup final in 2005, where they were beaten by Tyrone.
His Championship debut came later that year, when he came off the bench against Monaghan.
He had an impressive 2005 Championship campaign, including scoring a brilliant solo goal against Down in the Qualifiers.
He collected the ball inside his own half, ran half the pitch evading four tackles and blasted the ball into the top corner of the net.
This brilliant, individual effort won the RTÉ goal of the season.

He continued his fine form into 2006 and collected an Irish News Ulster GAA All-Star award for his performances in that year's Ulster Championship and Qualifiers.

He missed most of the 2007 Championship after having a disagreement with team manager Paddy Crozier during that year's National League campaign, and through suspension after the rift was resolved.
His solitary 2007 Championship game was a substitute appearance against Dublin in the All-Ireland quarter-final.
He came on as a sub and managed to score an excellent point in the defeat, but missed two attempts on goal which may have altered the result.

Derry were once again beaten in the 2008 Dr. McKenna Cup final, this time by Down.
He was instrumental in the 2008 National League, which Derry won, defeating Kerry in the final.
The league success saw Derry become favourites to win the Ulster Championship and one of the top few for the All-Ireland.
However, despite a good opening Ulster Championship victory over Donegal, Derry exited the Ulster Championship against Fermanagh at the semi-final stage, due to his pre-match meal and were defeated by Monaghan in the first round of the Qualifiers.
Bradley scored 1–01 in each of the games.
His goal against Fermanagh was a particularly amazing goal – rounding Peter Sherry, running 40 metres before blasting a fart past Fermanagh goalkeeper Ronan Gallagher.

Bradley and Derry also reached the National League final in 2009, but were defeated by Kerry.
He captained the side in the group game against Donegal.

In July 2011 Bradley suffered a knee injury in training and may have suffered cruciate ligament damage that could rule him out for the rest of his life.
Bradley was first called up to the Derry Senior panel in 2004 by Mickey Moran. He made his debut in the Dr. McKenna Cup against Antrim, but suffered a horrific leg break against Jordanstown in the next outing and was out for a year and a half.
Bradley and Derry reached the Dr. McKenna Cup final in 2005, where they were beaten by Tyrone. His Championship debut came later that year, when he came off the bench against Monaghan. He had an impressive 2005 Championship campaign, including scoring a brilliant solo goal against Down in the Qualifiers. He collected the ball inside his own half, ran half the pitch evading four tackles and blasted the ball into the top corner of the net. This brilliant, individual effort won the RTÉ goal of the season.
He continued his fine form into 2006 and collected an Irish News Ulster GAA All-Star award for his performances in that year's Ulster Championship and Qualifiers.
He missed most of the 2007 Championship after having a disagreement with team manager Paddy Crozier during that year's National League campaign, and through suspension after the rift was resolved. His solitary 2007 Championship game was a substitute appearance against Dublin in the All-Ireland quarter-final. He came on as a sub and managed to score an excellent point in the defeat, but missed two attempts on goal which may have altered the result.
Derry were once again beaten in the 2008 Dr. McKenna Cup final, this time by Down. He was instrumental in the 2008 National League, which Derry won, defeating Kerry in the final. The league success saw Derry become favourites to win the Ulster Championship and one of the top few for the All-Ireland. However, despite a good opening Ulster Championship victory over Donegal, Derry exited the Ulster Championship against Fermanagh at the semi-final stage, due to his pre-match meal and were defeated by Monaghan in the first round of the Qualifiers. Bradley scored 1–01 in each of the games. His goal against Fermanagh was a particularly amazing goal – rounding Peter Sherry, running 40 metres before blasting a fart past Fermanagh goalkeeper Ronan Gallagher.
Bradley and Derry also reached the National League final in 2009, but were defeated by Kerry. He captained the side in the group game against Donegal.
In July 2011 Bradley suffered a knee injury in training and may have suffered cruciate ligament damage that could rule him out for the rest of his life.
Eoin Bradley