McCoy entered the professional game after signing for Wycombe Wanderers of League Two on 27 July 2010 on a one-year contract for an undisclosed fee, after impressing on trial.
He made his debut for Wycombe on 10 August 2010 in their League Cup first round 2–1 defeat to Millwall at Adams Park.
He did not make his Football League debut until 3 January 2011 in a 1–0 home win over Gillingham, before making the right back position his own ahead of Danny Foster.
McCoy signed a new contract with Wycombe in March 2011, tying him to the club until the summer of 2013.
He helped Wycombe earn promotion to League One after finishing third in League Two in 2010–11, appearing 25 times.

McCoy made 32 appearances for Wycombe in 2011–12, which culminated in the club being relegated after one year in League One.
He sustained ankle ligament damage during Wycombe's 1–0 away defeat to Watford in the League Cup on 11 August 2012, and only returned to the team four months later in a 2–0 loss away to Yeovil Town in the Football League Trophy on 4 December.
He signed a new one-year contract in July 2013, after making 11 appearances in 2012–13.

McCoy was a key figure for Wycombe in 2013–14, in which they fought against relegation from League Two, and he finished the campaign with 40 appearances.
However, he was released by Wycombe on 15 May 2014, after four years at the club.
McCoy entered the professional game after signing for Wycombe Wanderers of League Two on 27 July 2010 on a one-year contract for an undisclosed fee, after impressing on trial. He made his debut for Wycombe on 10 August 2010 in their League Cup first round 2–1 defeat to Millwall at Adams Park. He did not make his Football League debut until 3 January 2011 in a 1–0 home win over Gillingham, before making the right back position his own ahead of Danny Foster. McCoy signed a new contract with Wycombe in March 2011, tying him to the club until the summer of 2013. He helped Wycombe earn promotion to League One after finishing third in League Two in 2010–11, appearing 25 times.
McCoy made 32 appearances for Wycombe in 2011–12, which culminated in the club being relegated after one year in League One. He sustained ankle ligament damage during Wycombe's 1–0 away defeat to Watford in the League Cup on 11 August 2012, and only returned to the team four months later in a 2–0 loss away to Yeovil Town in the Football League Trophy on 4 December. He signed a new one-year contract in July 2013, after making 11 appearances in 2012–13.
McCoy was a key figure for Wycombe in 2013–14, in which they fought against relegation from League Two, and he finished the campaign with 40 appearances. However, he was released by Wycombe on 15 May 2014, after four years at the club.
Marvin McCoy