Two men were injured when a melee erupted in a quiet Nelson street, Burnley Crown Court was told.
Mr Justin Evans was kicked and punched when he tried to quell the fight involving his stepson Mr Stephen Mulrooney, who was also punched.
The court heard Mr Mulrooney and defendant Jed Kemp, then 20, had had a dispute in a pub, and Kemp had arrived at Rowland Avenue with others in a car driven by co-defendant Donald Conelly.
Kemp had phoned ahead, telling Mr Mulrooney he would smash the windows of the family home if he did not come out on the street.
Kemp, of Casserley Road, Colne, and Conelly (22), of Every Street, Brierfield, admitted being involved in the affray which brought neighbours from their houses.
Conelly threw a punch at Mr Evans, knocking him to the ground. As he lay there Kemp kicked or stamped on his head. Injuries included a fractured eye socket and partial loss of vision. Kemp admitted wounding and was jailed for 25 months, with six months concurrent for the affray. Conelly, who until then had an unblemished character, also admitted throwing a punch at Mr Mulrooney, bursting his lip.
Sentencing, Mr Recorder Philip Parry said, although Kemp had an admirable work ethic, he had used gratuitous violence on a vulnerable man, and custody was inevitable.
He told Conelly that, after being roped in, he had been foolish in the extreme, both as a family man and as someone well regarded by his employer who had given the court an impressive reference.
Conelly admitted actual bodily harm and was given 12 months jail, suspended for a year and ordered to carry out 180 hours of community service. He must also pay £500 each to Mr Mulrooney and Mr Evans as compensation for their injuries.