Cardiff striker Michael Chopra is out after injuring his ankle in their 4-0 win against Doncaster Rovers.
Chopra is joined in the treatment room by defensive pair Kevin McNaughton (hamstring) and Darcy Blake (ankle), who also limped out of the game.
MATCH FACTS
Head-to-head
• This is the 24th competitive meeting of these clubs. Peterborough have won 12 of the previous 23, Cardiff were victorious five times, and six were drawn.
• Cardiff have not beaten Posh at London Road for 24 years, since a 2-1 triumph in the old Fourth Division in October 1986.
• This is their first-ever meeting in the League Cup.
Peterborough
• Peterborough enjoyed their best League Cup performance in 16 years by reaching the fourth round last season, when they beat Ipswich and Newcastle at London Road.
• The 1966 losing semi-finalists have played 150 ties in this competition, and won exactly 50 of them.
• The last time Posh lost a home tie in the League Cup was in the second round in 2007, to West Brom.
• They are chasing a fourth successive home win, which would keep their 100% London Road record this season intact.
Cardiff
• Cardiff, also losing semi-finalists in 1966, have reached the third round in all but one of the last six years.
• They were last knocked out by lower-league opposition four years ago, when League Two side Barnet defeated them 2-0 at Ninian Park.
• Dave Jones's side are chasing a fourth successive victory in all competitions.
• If selected, Peter Whittingham will be making his 250th club career appearance.
Source: BBC Sport
Source: BBC Sport