Sheffield United's hopes of sealing automatic promotion suffered another blow as they were held by gritty Plymouth.

Argyle found themselves under the cosh for much of the first half but United were unable to break down a resolute home side.

The Blades, determined to get their promotion charge back on track after a shock 4-1 reverse to Watford last time out, started strongly.

They won a free-kick after just two minutes but when Alan Quinn swung the ball over from the right, Nick Chadwick was on hand to clear the danger.

Just a minute later Neil Warnock's side gained the opening corner of the match, taken by Quinn, but it was cleared at the near post by Chadwick.

The visitors continued to push, though, with Chris Morgan's overhead effort on goal saved by Plymouth keeper Romain Larrieu.

Having weathered that early onslaught Plymouth gained their first corner after 11 minutes but Tony Capaldi's inswinger was comfortably dealt with by the United defence.

Larrieu was again in the thick of the action after 21 minutes when he did well to deny Ade Akinbiyi from close range, but just seconds later Plymouth had a chance only for Micky Evans to be denied by defender Chris Morgan's timely intervention.

The home side were then presented with a gilt-edged opportunity to open their account shortly before the half-hour.

An Anthony Barness cross from the right was met just six yards out by Chadwick but he directed his header wide.

Plymouth's confidence continued to grow and visiting goalkeeper Paddy Kenny had to be on his toes to keep out a 20-yard shot from David Norris.

The visitors then carved out another chance when Quinn's corner found Leigh Bromby but he was unable to direct his close-range header on target.

Just before the break Larrieu made another fine save to keep out Phil Jagielka's header.

Sheffield United created the first chance of the second half but Quinn's well-struck left-footed shot from 12 yards was blocked by Mathias Doumbe after 53 minutes.

Plymouth made a switch just five minutes later, bringing on Vincent Pericard for Evans.

But it was the visitors who again threatened to break the deadlock on the hour, with Larrieu again to Plymouth's rescue as he kept out Akinbiyi's header from six yards.

As play continued to switch from end to end Pericard swiftly made his presence felt by firing in a shot from 12 yards but it cleared the crossbar.

United also made a change with 19 minutes remaining, bringing on Keith Gillespie in place of the injured Quinn and subsequently replaced Steve Kabba with Neil Shipperley and Garry Flitcroft with Nick Montgomery.

But it proved to no avail as the home side held on for a share of the spoils.

Plymouth could even have won it at the death, but Kenny superbly tipped a Norris shot around the post.

Plymouth Larrieu, Connolly, Doumbe, Ward, Barness, Norris,Wotton, Nalis, Capaldi, Evans (Pericard 58), Chadwick.

Subs Not Used: McCormick, Buzsaky, Aljofree, Hodges.

Booked: Nalis, Doumbe.

Sheff Utd Kenny, Bromby, Short, Morgan, Armstrong, Ifill,Jagielka, Flitcroft (Montgomery 77), Quinn (Gillespie 71),Akinbiyi, Kabba (Shipperley 76).

Subs Not Used: Barnes, Kozluk.

Att: 15,017

Ref: C Penton (Sussex).