Sheffield United captain David Holdsworth scored his third vital goal in four games to help set up a money-spinning fifth round clash at Arsenal.

Holdsworth's 52nd-minute scrambled effort sparked a rampant second-half performance.

The last 16 tie at Highbury was sealed six minutes later when 18-year-old substitute Lee Morris rammed home his first goal for the club.

Marcelo and Graham Stuart then both went close before the former Chelsea and Everton midfielder drove home the fourth off the legs of keeper Jon Hallworth, who had earlier proved the hero.

United could have been four goals clear by the time Kevin Nugent headed a 19th-minute equaliser, but for the agility of Hallworth.

The visitors goal was all credit to leading scorer John Williams, who chased a lost cause and managed to hook it over his head for Kevin Nugent to nod home his 12th of the season.

Sheff Utd: Kelly, Borbokis (Ford 60), Quinn, Derry, Sandford, Holdsworth, Woodhouse (Henry 78), Twiss (Morris 46), Marcelo, Devlin, Stuart. Subs Not Used: Tracey, Jacobsen. Goals: Devlin 13, Holdsworth 52, Morris 58, Stuart 68.

Cardiff: Hallworth, Delaney, Ford, Mitchell, Eckhardt, Carpenter, Fowler, O'Sullivan (Legg 60), Williams (Bowen 60), Nugent, Middleton (Hill 65). Subs Not Used: Thomas, Kelly. Booked: Middleton. Goals: Nugent 19.

Referee: J Winter (Stockton-on-Tees).