United twice came from behind to draw 2-2 with Burton after extra-time at Bramall Lane. Adi Yussuf gave visitors Burton the lead in the 33rd minute, with Nick Blackman equalising for the hosts five minutes into the second half.

Cleveland Taylor restored Burton's advantage six minutes into the additional 30, this time it was Neill Collins' turn to get United back on level terms.

The comeback was ultimately to no avail, as Burton ran out 5-4 winners in the resulting shootout.

Elsewhere on Saturday, Wolverhampton Wanderers, relegated from the English Premier League last season, were held 1-1 at home to lowly Aldershot Town, but progressed courtesy of a 7-6 shootout win.

Hull City too were fortunate to advance, also winning 7-6 on penalties following a 1-1 draw at home to Rotherham.

In other matches, goals from Marvin Emnes and Grant Leadbitter helped Middlesbrough get past 10-man Bury 2-1 away from home.

Matty Robson's strike was enough for Carlisle United to down Accrington Stanley 1-0, while two goals apiece from Max Clayton and Mathias Pogba helped Crewe Alexandria smash Hartlepool 5-0.

Doncaster Rovers came from behind to draw 1-1 with York City, before reaching the next round 4-2 on penalties.

New signing Luke Varney was on target as Leeds dispatched visiting Shrewsbury 4-0, and Bradford City won 1-0 at Notts County.

Barnsley survived going down to 10 men as they beat Rochdale 4-3 in extra-time.

Finally, Walsall downed Brentford 1-0 at home, and Watford overcame Wycombe by the same scoreline.