John Oster gave Grimsby's hopes of avoiding relegation a shot in the arm with a double to secure victory against Derby at Pride Park.

The on-loan Sunderland winger gave the Mariners the perfect start after three minutes when he headed home a cross from Terry Cooke after a neat ball from Simon Ford.

Former Sheffield United striker Lee Morris levelled for the Rams after 32 minutes with a fine solo effort, but Oster struck again with a free-kick on 64 before substitute David Soames scored his first goal for the club one minute from time.

Town player-boss Paul Groves, returning to the starting line-up after dropping himself for the win over Sheffield Wednesday, almost doubled the lead with a header minutes after Oster's opener.

County midfielder Rob Lee, back from suspension in place of youngster Izale McLeod, missed the target with a 20-yard volley, while Morris failed to test Town keeper Danny Coyne from just outside the area.

Adam Bolder forced Coyne into making a save midway through the half with a smart strike as the Rams pressed for an equaliser their efforts deserved.

Lee was always in the thick of the action and Coyne had to be on his toes to keep out another long-range effort from the former Newcastle midfielder after half an hour.

But Morris levelled two minutes later when the striker picked the ball up inside his own half and finished off a dazzling run with a fine left-foot finish into the top corner.

Groves made four changes to the side that beat Sheffield Wednesday 2-0, but the Division One strugglers looked capable of scoring on the counter-attack and Darren Mansaram forced Derby keeper Lee Grant into action with a smart strike eight minutes before the break.

But Derby finished the half strongly, with Christie drilling a fierce 30-yard strike over the crossbar.

Rams boss John Gregory made two changes at the break as he sought to breach the Town defence, with Giorgi Kinkladze and youngster McLeod replacing Ian Evatt and Bolder respectively.

And the second half started in similar fashion to the first, with Grimsby on the back foot against a team looking to bounce back from their 3-0 defeat at Coventry.

Morris and Warren Barton both fired in shots which failed to trouble Coyne, before Oster grabbed his second from a set-piece.

Oster whipped in a fierce right-footed free-kick from the left after he had been fouled by Barton and watched his effort sail into the top right-hand corner.

The home side pressed forward in search of a leveller, with Christie volleying wide, while Barton's 30-yard strike was kept out by former Tranmere net-minder Coyne.

But David Soames sealed the points for the visitors only three minutes after coming on as an 86th-minute substitute for Darren Mansaram.

Grimsby broke away after clearing a corner in the dying stages and Soames drilled into the bottom corner in only his fourth appearance to give the Mariners their second successive victory.

Teams:

Derby Grant, Barton, Riggott, Evatt (McLeod 46), Elliott, Boertien (Holmes 76), Burley, Lee, Bolder (Kinkladze 46), Christie, Morris.

Subs Not Used: Oakes, Mills.

Goals: Morris 32.

Grimsby Coyne, Ward (Bolder 72), Chettle, Gavin, Ford, Cooke (Parker 56), Groves, Santos, Campbell, Mansaram (Soames 86), Oster.

Subs Not Used: Thompson, Allaway.

Booked: Gavin, Campbell, Mansaram, Santos.

Goals: Oster 3, 64, Soames 89.

Att: 27,141

Ref: M Fletcher (Worcestershire).