Newcastle United have progressed to the fifth round of the FA Cup following a 3-2 win against Birmingham City at St Andrew's.

Ethan Laird's volley gave the League One leaders the dream start inside a minute, but quickfire goals from Joe Willock and Callum Wilson turned the game on its head midway through the first half. Birmingham came roaring back, though, following a thunderbolt from Tomoki Iwata before Willock struck late on to send Newcastle into the last 16.

Here are five things we learned from the game.

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Newcastle come through physical test

The best sides do it. Regardless of the competition, the venue or the turnaround, they get the job done. That is the team Newcastle aspire to be.

Less than 72 hours after reaching the Carabao Cup final, could Newcastle quickly refocus on the task at hand after Eddie Howe made nine changes? Could Newcastle prove they were a 'really powerful beast' as Birmingham City boss Chris Davies called them?

No wonder Howe stressed this match would come down to 'attitude' and 'knowing the importance of every duel' against an aggressive side who also like to press high and get in the face of the opposition. This was a dogfight at times.

It said it all that when Dan Burn went off with what looked like a groin injury in the 55th minute, replacement Fabian Schar had not long been on the field when the Newcastle defender had his shirt pulled by Jay Stansfield and was sent crashing into the advertising hoardings.

The game became a stop-start affair as a physical Birmingham side threw their weight around. Ben Davies went into the back of William Osula yet did not even get booked. Lyndon Dykes had just come on when he shoulder-barged Emil Krafth to the ground. Willum Willumsson left Joe Willock hobbling after catching the midfielder with a slide tackle as he skipped away from him.

However, Newcastle, and Willock, did not lose their heads and the persistent midfielder ended up scoring the winner in the 82nd minute. Willock started the move off when he peeled off the left-hand side and squared the ball to Tino Livramento. The Newcastle right-back slipped Sean Longstaff in down the overlap and the midfielder's cross was met by Willock, who drilled the ball through Bailey Peacock-Farrell's legs to keep another route to Wembley open.

Callum Wilson makes his mark

May 4. That was the last time Callum Wilson started a competitive game for Newcastle. You suspect Wilson was desperate to make up for lost time after a series of frustrating injuries. Wilson certainly did that.

When Newcastle needed someone to step up at St Andrews, Wilson grabbed the game by the scruff of the neck midway through the first half. Wilson expertly spun away from Ben Davies inside the centre circle before bundling past Christoph Klarer and swinging a teasing cross towards the back post to Osula. The Dane drilled the ball back across and Willock caught it first-time. Although Bailey Peacock-Farrell managed to get a hand to it, the assistant ruled the ball had crossed the line.

Wilson was not finished yet. If the first goal showcased one aspect of Wilson's game - the strength, the pace, the experience - the second was a trademark poacher's finish.

There were 26 minutes on the clock when William Osula burst down the right before unleashing a venomous effort that was pushed away by Bailey Peacock-Farrell. Osula was first to the ball and played it back to Sean Longstaff, who slipped Tino Livramento in down the overlap. Although Willock and Osula failed to knock in the defender's cross. Wilson was there to hook it in at the third time of asking.

Another shock spared

There was a reason why this game was picked by the BBC. There may have been two divisions separating Newcastle and Birmingham City, but broadcasters smelt a potential upset. Alan Shearer admitted as much. "You know the reason the cameras are here," he said. "It's just in case there's an upset."

Newcastle simply could not afford to take Birmingham lightly, particularly at a rocking St Andrew's. Fearless Birmingham had forgotten how to lose, after embarking on an 18-game unbeaten run, and the League One leaders had suffered just one defeat at home all season. Newcastle needed no reminding of the perils of such FA Cup ties; the Magpies were taken to penalties by Blackburn Rovers last season, knocked out by Sheffield Wednesday a couple of years ago and humbled by Cambridge United 12 months before that. However, it was Birmingham City who raced out of the blocks.

It took Birmingham just 18 seconds to win a corner kick - and the Blues took full advantage after the unmarked Keshi Anderson was able to head the ball back across. There was Ethan Laird to catch it on the volley and send the hosts into dreamland as the home support taunted: "Who are ya? Who are ya?"

Newcastle rallied to flip the game on its head, but you could see why Birmingham had recovered more points from losing positions than any other side in England's top four divisions. The hosts came roaring back and levelled courtesy of a screamer from Tomoki Iwata just before half-time only for Joe Willock to land a knockout blow late on.

William Osula not cowed by Birmingham City

This was William Osula's third competitive start for Newcastle. It was just the Dane's first outing on the right wing for the club. Yet you would not have known it. As well as playing a role in both of Newcastle's goals, the forward stood up to the physical challenge against the League One leaders.

At one point, after the half-hour mark, Osula spun away from Alex Cochrane and was knocked to the floor by Marc Leonard. Rather than appeal for a foul, Osula immediately got back to his feet, won the ball back and managed to win a free-kick despite having three blue shirts around him.

When Jay Stansfield knocked Osula to the turf, just before half-time, the 21-year-old got to his feet and confronted the Birmingham striker. That was the cue for four Birmingham players to surround Osula before Bruno Guimaraes, Emil Krafth, Dan Burn, Tino Livramento and even Nick Pope rushed on to the scene.

Osula was booked for his troubles and Sean Longstaff took his team-mate aside to tell him to calm down, but this is a forward who plays right on the edge. It said it all that one of Osula's first involvements in the second half was to knock Keshi Anderson to the ground after the strong Birmingham defender merely bounced off him.

Nick Pope sends a timely reminder

Things can quickly change in football. One of the few certainties going into this campaign was that Nick Pope would line up between the sticks for Newcastle, but it now appears to be Martin Dubravka's shirt to lose after the Slovakia number one took his chance in his team-mate's absence.

Dubravka has kept seven clean sheets in 13 games since Pope suffered a knee injury in December and it was rather telling that the veteran kept his place - even after his fellow shot-stopper returned to the match day squad last month. Pope knew he had a battle on his hands and, having impressed with some 'very strong' performances in training, this was a rare opportunity for the 32-year-old to stake a claim in his first appearance in two months.

Pope barely had a second to catch his breath. After conceding inside 60 seconds, Pope booted the ball out of play in the opening stages. It summed up a shaky start from Newcastle.

However, Pope offered a timely reminder of his qualities to keep Newcastle in the game at 1-0 down. It was a carbon copy of Birmingham's first as a set-piece was headed back across and, this time, Keshi Anderson caught it on the volley, but Pope made a huge reflex save to push the ball away. It was a crucial stop. Newcastle were level just a few minutes later.

Pope made another big save shortly after Newcastle went 3-2 up late on. Newcastle failed to deal with a Birmingham corner and the ball bobbled across, but Pope managed to stick out a foot to keep it out.