[3][4] Born in Dublin, Connolly inherited a passion for sport from his Kilkenny-born father and County Clare-born mother.
After an unsuccessful minor tenure, he later joined the Dublin under-21 teams as a dual player and won a Leinster medal as a hurler.
In June 2017, Connolly received a 12-week ban after physical interference with linesman Ciaran Branagan during Dublin's win against Carlow in the quarter-final of the 2017 Leinster Senior Football Championship.
[2] Connolly pleaded guilty to assault causing harm during an unprovoked attack at a pub in Phibsborough on 6 August 2012.
In October 2014, District Court Judge Patrick Clyne dismissed the case "because Connolly had done all that had been asked of him through a series of restorative justice measures".
[9] Connolly again pleaded guilty to assault after paying €2,000 compensation to two men who were punched by him in what was described as an unprovoked attack on New Year's Eve in 2022.