A GOAL in each half was enough as Derby County overcome a dogged Chesterfield to secure their place in the Fifth Round of the FA Cup.
Darren Bent, on his full debut, showed his poacher instincts to flick in the opener midway through the first half, before the contest sparked to life in the second 45 minutes with both sides throwing everything at the game.
It was not until Will Hughes scored with eight minutes remaining that Derby could relax as a plucky Spireites side pushed the Rams all the way at the iPro Stadium.
Backed by a boisterous crowd of just under 5,500 travelling supporters, Chesterfield settled into the contest the quicker, controlling larger periods of possession and forcing the Rams to sit back inside their half.
With the pressure, though, the defensively trio of Richard Keogh, Raul Albentosa and Jake Buxton, Derby held the Spireites at arms length.
At the other end, the Rams looked to utilise that pace of Darren Bent, who was always leaning on the shoulder of his last man, and the striker was narrowly caught out on curled ball forward and the second had Sam Hird stretching to block Will Hughes’ threaded ball.
The visitors had their first real opening as a long ball caught out Keogh and sent Armand Gnanduillet through, but his tame curled effort was easily held by Kelle Roos in the Derby goal.
Five minutes later and the Rams broke the scoring to edge in front.
After winning a corner on the right, Omar Mascarell whipped the ball on to the head of fellow Spaniard, Albentosa, whose goalbound header was turned in by Bent for a goal on his full debut.
The flow of the contest continued in the same vein as Chesterfield, patiently, passed the ball in between the lines, but it was not too long before they began to carve out openings.
James O’Shea flashed a fierce effort narrowly wide from the edge of the area and forced Roos into a save with two chances in as many minutes, before Sam Clucas, the hero for the Spireites in the last round, also blazed wide.
Doyle flashed a first time effort over the top of Roos’ bar as the visitors continued to control proceedings and with that, Steve McClaren looked to swing the pendulum back into his side’s favour at half time.
On came Johnny Russell as the Rams tweaked their formation and it nearly paid dividends with six minutes of the restart.
On 51 minutes, the home side should have doubled their lead as Bent, hanging on the last man again, escaped down the middle with just Tommy Lee to beat, but the ‘keeper stood tall to deny the forward.
In a frantic spell, Chesterfield played their way out of trouble and made headway towards the Derby box.
After dealing with a series of corners, O’Shea, after brilliantly evading two challengers, lifted the ball into the air to set up a volley, but Roos got his body in the line of the shot for a corner.
In breathless fashion, just as Bent did five minutes earlier, Hughes carved open the Spireites’ backline to set Russell away, who, like Bent, was also denied by Lee.
Doyle then shot wide from the right and Bent, after Charlie Raglan did not get a clean header on a ball forward, tried to lob the advancing Lee, but the ‘keeper again got enough on the ball to turn it away.
At the other end, Jimmy Ryan blazed over with a first time effort after a left wing cross flew across the Rams’ backline.
With 20 minutes remaining, McClaren made his final change and introduced Simon Dawkins and within seconds the Jamaican international cracked the top of the bar after connecting with Jamie Ward’s cross from the right.
Doyle tamely shot into the midriff of Roos as the game entered its final 15 minutes as the Spireites as they piled the pressure on the Rams’ backline, but after holding strong, Derby killed the tie off.
After Bent’s initial effort was blocked, Hughes robbed Morsy of possession and drove into the area before slipping a right-footed shot over Lee with 10 minutes remaining.
The Derby backline stood firm as Paul Cook’s Chesterfield applied late pressure, but the damage had already been done on a day when shocks swept across the FA Cup, but the Rams were not to be one of them as they secured their place in Monday’s draw for the Fifth Round.
Derby County: Roos, Keogh, Albentosa (Russell, 46, Ward, 65), Buxton; Christie, Forsyth, Mascarell, Hughes, Hendrick; Bent, Martin (Dawkins, 71)
Substitutes not used: Mitchell, Bryson, Shotton, Warnock
Chesterfield: Lee (GK), Darikwa, Jones, Hird, Morsy, Ryan (Banks, 75), Gnanduillet (Diesuruvwe, 88), O'Shea (Gardner, 75), Clucas, Raglan, Doyle
Substitutes not used: Wright, Humphreys, Evatt, Talbot
Attendance: 28,392 (5,433 away fans)