Norwich City 4, Sheffield United 2

The Blades led 2-1 at the interval against the out-of-sorts Canaries, but Hoolahan, introduced at half-time, kept his cool with two penalties to turn the game round in front of a Carrow Road crowd of nearly 26,000, then he wrapped up victory in stoppage time when he completed his treble from a pass by skipper Grant Holt, after the Blades had been reduced to 10 men by the sending-off of Stephen Quinn.

It was three more valuable Championship points for Paul Lambert's men but for once they had the rub of the green after a poor first-half showing.

United went ahead from an Andy Reid free-kick after 17 minutes, Michael Nelson heading the equaliser from David Fox's free-kick two minutes later.

Richard Cresswell restored United's lead after 29 minutes and City were struggling to get on terms until referee Phil Crossley awarded the first penalty, after 64 minutes, as Holt went down under challenge from Blades skipper Nick Montgomery.

Hoolahan scored again from the spot six minutes from time, the penalty awarded for handball, and Quinn was shown the red card in time added on before the Irishman struck his third of the afternoon.

There were two changes to the City starting line-up from the 2-1 victory at Coventry 10 days earlier.

Defender Elliott Ward and midfielder Henri Lansbury were absentees from the squad of 18, so Jens Berthel Askou was recalled in defence with Andrew Crofts returning in midfield after a bout of flu'.

The two defenders on the bench were full-back Adam Drury, after more than two months out with a calf injury, and Zak Whitbread, involved in the senior squad for the first time this season after a long battle against calf and hamstring problems.

The United line-up included striker Ched Evans, who scored 10 goals during a loan spell with the Canaries three seasons ago, and struck both for the Blades in the 3-2 home defeat by Hull on Boxing Day.

City adopted an unorthodox formation with Russell Martin operating behind the two centre-halves and Korey Smith and Lappin operating more as wing-backs.

There was a narrow escape for United in the third minute when Nosworthy diverted a cross from Holt on to the post.

From the corner that followed Nelson headed over the top from a Fox kick.

United had their first effort on goal in the 13th minute when Evans and Reid combined well but Yeates, with plenty of space, pulled a left-foot shot wide of the target.

United took the lead, however, in the 17th minute when Reid scored direct from a free-kick.

Askou was penalised for a foul on Evans just outside the Norwich penalty area and with two players standing over the ball, Yeates allowed Reid to step up and curl a perfect left-foot shot into the top corner out of Ruddy's reach.

City were level inside two minutes, however, when defender Nelson scored his second goal of the season, also from a free-kick, awarded for a foul on Chris Martin. Fox floated in the dead-ball kick from the right and Nelson rose unmarked to power a header past Simonsen.

United should have regained the lead immediately, however, when it took a great last-ditch challenge by Russell Martin to deny Evans after the same player had given the ball away on the edge of the penalty area.

Nelson threatened again when he rose at the far post to head just off target from Lappin's cross, then Holt was just wide with a header from a Fox corner.

City appeared to have reverted to a more orthodox back four with Russell Martin at right-back, after looking uncertain in the opening quarter of the match.

United regained the lead, however, in the 29th minute with the simplest of goals from Cresswell.

Yeates dummied Quinn's pass and Cresswell was given far too much time to swivel and fire a right-foot shot inside the post.

Four minutes before the break, United were appealing for a penalty as Evans went down under challenge from Nelson but the ex-Canary was instead penalised for a foul.

Bartley was booked in first-half stoppage time for a foul on Holt.

• HALF-TIME: Norwich City 1, Sheffield United 2

There was a change at the interval with Hoolahan replacing Jackson for his 100th appearance in City colours.

Three minutes after the break, Lappin was booked for a foul on Evans – his fifth yellow card of the season bringing a one-match ban.

Hoolahan came into the action on the hour when he took a return pass from Holt inside the United area but floated his attempted cross over the top.

Chris Martin won a corner when his shot was deflected out for a corner, but Hoolahan's kick was a poor one.

There was a second change when McNamee replaced Fox after 62 minutes.

And City were level in the 64th minute when substitute Hoolahan scored from the penalty spot.

Holt went down under challenge from Montgomery and referee Crossley pointed to the spot, though it appeared a harsh decision.

Montgomery was shown the yellow card and, after a short delay, Hoolahan tucked away the spot-kick left-footed.

Evans almost caught out Ruddy with an audacious effort from the halfway line that nearly swirled under the bar, but as City hit back, Simonsen made an important save from Chris Martin after Nelson had knocked on Askou's free-kick.

Cresswell ballooned an effort off target when he might have done better as the Blades hit back.

A cross by McNamee to the near post was close to providing Holt with a decent chance but Simonsen did well to make a catch under pressure from the City skipper.

Askou then got on the end of a free-kick by Hoolahan but his header lacked power.

Evans fired into the crowd as United looked for a winner, but it was the Canaries who instead nudged ahead with six minutes left.

Bartley appeared to be the man penalised for handball as Korey Smith attempted a one-two with Chris Martin, and referee Crossley again pointed to the spot.

Hoolahan stepped up to coolly score from the penalty spot, but was then booked for his celebration.

There was a final change for City when Whitbread replaced substitute McNamee and, in the final minute, further controversy when Nelson protested about a high challenge by Lowton.

In stoppage time, there was a further clash between players on both sides and Quinn was shown the red card.

Ruddy made a brilliant save from Evans to keep City ahead, then with nearly seven minutes added time played, Holt set up Hoolahan to make it 4-2.

• RESULT: Norwich City 4, Sheffield United 2

• Norwich City: Ruddy; Nelson, Russell Martin, Askou, Korey Smith, Crofts, Fox (McNamee, 62, Whitbread 89), Lappin; Jackson (Hoolahan, 45); Chris Martin, Holt. Subs (not used): Rudd, Drury, Tudur Jones, Johnson.

• Sheffield United: Simonsen; Calve (Bogdanovic, 87), Bartley, Nosworthy, Lowton; Yeates, Montgomery, Quinn, Cresswell; Reid; Evans. Subs (not used): Wright, Ertl, Williamson, Jamie Ward, Kozluk, Batth.

• Referee: Phil Crossley (Kent)

• Attendance: 25,809

• Goals: City: Nelson (19), Hoolahan (pen 64, pen 84, 90). United: Reid (17), Cresswell (29)

• Red card: United: Quinn (90)

• Bookings: City: Lappin (48), Hoolahan (84). United: Bartley (45), Montgomery (64)