Rotherham United booked their place in the League One playoff final after a 3-1 victory over Preston North End.
The Millers were level at 1-1 with Preston following the first leg of their semi-final but progressed to the showpiece Wembley final 4-2 on aggregate.
Victory against Leyton Orient would secure Rotherham their second consecutive promotion after they went up automatically last season.
The result was a boon for manager Steve Evans, whose controversial past has often overshadowed his side's on-field success.
During his spell at Boston United, Evans avoided being sent to jail after pleading guilty to charges of cheating public revenue which helped the club to promotion to the Football League.
Amid a string of charge from The Football Association, in 2012 he was accused of exposing himself to a female member of staff from Bradford City following his Crawley Town side's acrimonious match against the Bantams.
He was eventually given a six-match stadium ban and fined £3,000 after being found guilty of using abusive and insulting words and behaviour with a reference to gender.