Gareth Davis reports from Pride Park Stadium
Chris Porter opened his goalscoring account for Derby but it was a night of frustration at Pride Park as the home side were forced to settle for a 2-2 draw with Swansea City.
The former Motherwell man had poked home the opener just 12 minutes in as he capitalised on a loose ball after Robbie Savage's free-kick was saved by Dorus De Vries.
And two minutes after the interval, when Porter raced clear to add the second, Derby looked to be taking command.
Angel Rangel quickly got the visitors back in it, though Steve Davies and Gary Teale both saw shots cannon back off a post later in the game.
It was all-square with three minutes on the clock through substitute Gorka Pintado as the visitors recovered strongly to take a point back to South Wales.
Rams boss Nigel Clough kept the same squad that went down 2-1 at Doncaster Rovers on Friday night for Derby's first home league game with Swansea in over two decades.
He was still without the injured Kris Commons, Miles Addison and Nacer Barazite so named the same starting line-up and the same five substitutes as at the Keepmoat Stadium.
It was the same shape from the off too with Gary Teale starting on the left wing and Steve Davies to the right, though the pair have the flexibility to swap at a moment's notice.
Swansea, looking to embark on another long unbeaten run to keep themselves in the play-off hunt, started brightly enough with some flowing football on a Pride Park surface given a bit of extra zip by the evening's heavy rain.
But they were soon under threat when Davies swung over an inviting corner from the right that Martin Albrechtsen looked set to reach in front of goal, only for a visiting head to clear at the vital moment.
And on ten minutes Chris Porter closed down Angel Rangel, sending Rob Hulse running towards the box, and he in turn fed Davies to his right but the young winger's shot from inside the area sailed safely over the target.
At the other end Stephen Bywater was soon called into action to show good handling and grab Jordi Gomez's skidding low drive, before Davies again came close.
Porter flicked on Teale's cross and it came to Derby's number 20, who perhaps took too long in lining up his shot and was denied by the legs of Dorus De Vries.
And when Davies was halted in his tracks after charging forward on 12 minutes, the Rams ended up taking the lead.
Robbie Savage lined up a free-kick in an almost identical position to his goal at Doncaster but this time he went around the wall rather than over it, and De Vries saved well.
But the ball came loose so it was all about who would react first - and in slid Porter to get the vital touch from close range and open his Rams account.
Swansea's response was swift through Gomez, who curled a long-range free-kick into the side-netting, though Bywater looked to have had the shot covered.
And the tricky Thomas Butler soon carved out a delightful low cross after a fine run that saw Bywater dive bravely at the feet of Nathan Dyer to clean up.
Derby again broke forward and on 19 they had strong penalty appeals waved away by referee Phil Crossley.
Hulse was sent into the box on a long ball and touched the ball away from the out-rushing De Vries before hitting the deck.
From a long distance and without the aid of a replay it was impossible to determine the legitimacy of the claim, but it appeared seconds later not to be Hulse's night when he saw a close-range finish ruled out for offside after Davies crossed low.
Crossley was hardly endearing himself to the home faithful, who were enraged when Porter was clattered on the edge of the box and required strapping to support a head wound.
But at least the official had lasted longer than on his previous visit to Pride Park. He was the man, you may remember, hospitalised after colliding with Seth Johnson on the final day of the 2006/07 season against Leeds United.
The Kent whistle-blower did, however, have no option than to wave a yellow card to Jay McEveley for the full-back's needless tackle on Dyer near the right touchline.
His second yellow card, for Swansea teenager Joe Allen, did appear somewhat harsh, though bookings were the only item of note wiith the game dying down a bit around the half-hour mark.
But with the clock reading 36 minutes Derby were close to going two clear.
Hulse's shirt was pulled by Albert Serran, giving Savage another free-kick in what was appearing his favourite position, and though the Welshman's shot went up over the wall and down the other side it flashed just past the post.
Swansea always looked dangerous going forward but they were almost caught out three minutes before the interval when Porter was sent clear and rounded De Vries.
The former Motherwell man was forced wide and his cross was just in front of Hulse, then as the visitors failed to clear Lewin Nyatanga thundered in a 30-yarder that De Vries had to grab at the second attempt.
Roberto Martinez's men were back on the front foot through skipper Alan Tate, who forced Bywater into a low stop from 20 yards, and they ended the half on top in terms of possession but unable to forge a clear chance.
And they were made to pay within two minutes of the restart as Derby doubled their lead.
A long ball was played up out of defence and nodded on by a Swansea head inito the path of Porter, who raced away from Ashley Williams and got into the box before finishing calmly past De Vries for his second of the night.
It may well have been three five minutes later through Hulse, who rose unchallenged to meet Paul Connolly's inviting cross but planted his header past the post when well-placed, then dragged a left-footer across goal after getting in behind the defence.
And the visitors were soon back in the game in rather fortunate style.
Gomez's right-wing free-kick was hammered goalwards by Angel Rangel and turned away by Bywater, only for it to strike the far post and find its way into the net.
Bywater then produced a couple of smart saves to deny Gomez as Swansea charged forward in search of a quick equaliser.
The visitors had their tails up and signalled their intentions to push on with a double substitution on the hour as Darren Pratley and Gorka Pintado took over from Dyer, fresh after picking up a yellow card, and Leon Britton.
However they were the width of a post away from going further behind again as Teale drove his way forward and slipped inside Rangel before smashing in a low one that beat De Vries and hammered away off the upright.
The second half seemed to be flying by and it was a surprise to see the clock reading 75 when Davies drove forward down the right and made ground into the box, only to be cut off well by Tate.
And four minutes later Davies was heavily involved again after being found superbly by Paul Green, who seemed to be getting stronger as the game went on.
This time the youngster cut inside on to his left foot and beat De Vries with a powerful shot that hit the post and came out too quickly for Hulse to react and prod it into an empty net, such was the pace on the initial shot.
Swansea began to pile men forward in search of an equaliser and they had a spell of peppering the Derby box with crosses, though one low deviation almost produced dividends as Pratley's shot was deflected just past the post.
They did tie it up with five to go as Jason Scotland was played in behind the defence and slipped a low ball back for Pintado to hammer a 14-yarder in off the crossbar.
Then they were thankful to goalkeeper De Vries, who showed all of his agility to stretch back and turn Green's stunning volley over the crossbar after it had looked destined for the back of the net.
It would have been a dramatic way to end a game that could, on the balance of play, have gone to either side.
Derby County: Bywater, Connolly (C), McEveley, Green, Savage, Hulse, Nyatanga, Davies, Teale, Albrechtsen, Porter.
Substitutes: Carroll (GK), Villa, Varney, Sterjovski, Todd.
Booked: McEveley (24, foul).
Swansea City: De Vries, Williams, Tate (C), Britton (Pratley 59), Scotland, Gomez (Orlandi 77), Rangel, Allen, Serran, Butler, Dyer (Pintado 59).
Substitutes: Bauza, Collins.
Booked: Allen (29, foul), Dyer (59, unsportsmanlike conduct).
Attendance: 26,691 (462 visiting fans).