On-the-whistle report: Many happy returns for birthday boy Michael Smith ... Rotherham United 4 Portsmouth 1

The striker scored twice against one of his old clubs and has now hit the target ten times in his last 11 games.

It was the perfect way for him to mark a weekend which sees him turn 30 tomorrow.

An eight-minute, three-goal blitz by Paul Warne's men ended the contest in the second half after Portsmouth had equalised Smith's opener.

Rotherham remain in fifth spot but are unbeaten in their last six League One outings and are the team to fear  in the division.

The visitors has looked dangerous in the opening stages but were later overrun by a side gathering more and more momentum and belief.

Viktor Johnasson was called into action in the fifth minute as Shaun Williams' vicious shot from distance forced the Millers goalkeeper to concede a corner

The visitors took the game to Rotherham as they made a bright start but it was the home side who came closest to breaking the deadlock.

Rarmani Edmonds-Green was in the right place at the right time at the back post as he got on the end of Michael Ihiekwe's 18th-minute header across goal but Gavin Bazunu was on hand make a brave save.

The breakthrough came 11 minutes later and it was that man Smith doing the damage yet again.

Ollie Rathbone cleverly worked Wes Harding into a crossing position and the centre-forward's back-post header was as deadly as the wing-back's right-flank delivery.

In the warm autumnal sun, Pompey had looked as good as any side to come to New York this season, but Rotherham are a team to be reckoned with this season and gradually forced their way on top.

Rathbone led the charge, popping up here, there and everywhere, and the Millers were threatening a second goal as the second half came to a close.

Manager Warne had chosen to not to start either of his two players who had been away on senior international duty, meaning the threats of wide men Chiedozie Ogbene and Shane Ferguson were kept in reserve on the bench.

Pompey were without former Millers centre-half Clark Robertson, sidelined by a quad injury, but another New York old boy, Sean Raggett, was at the heart of their rearguard.

Rotherham appeared to be in control until they gifted Pompey an equaliser four minutes after the break.

Dan Barlaser had all the time in the world to clear but tried to be too clever. Ryan Tunnicliffe dispossed him on the left and fed Marcus Harness who showed pinpoint accuracy from the edge of the box.

Back came the Millers and within six minutes they were in front again as Smith went into double figures for the campaign.

Rathbone shot, Bazunu fumbled and Smith scored with a delightful back-heel after his initial attempt had been blocked.

Now Rotherham really turned the screw and the goals kept flying in at a kop end getting louder and more boisterous by the second.

Richard Wood opened his account for the campaign with a 60th-minute header and just three minutes later it was Ben Wiles' turn to send New York into raptures with a sweet finish.

Mickel Miller brought an excellent save from Bazunu as Pompey reeled under the Millers' onslaught, Wiles miscued in front of the net when his second goal of the afternoon was there for the taking and Barlaser almost caught out Bazunu with a free-kick.

The Millers continued to look dangerous right to the final whistle. 4-1. Not bad for a team that don't take enough of their chances!

Rotherham (3-5-2): Viktor Johansson; Rarmani Edmonds-Green, Richard Wood, Michael Ihiekwe (Chiedozie Ogbene 54); Wes Harding, Ben Wiles, Dan Barlaser, Ollie Rathbone, Mickel Miller; Will Grigg (Freddie Ladapo 68), Michael Smith (Josh Kayode 81). Subs not used: Josh Vickers, Hakeem Odoffin, Kieran Sadlier, Shane Ferguson.

Portsmouth (3-1-4-2): Gavin Bazuna; Kieron Freeman, Sean Raggett, Connor Ogilvie; Shaun Williams (Louis Thompson 73); Mahlon Romeo, Ryan Tunnifcliffe (Reeco Hackett 73), Joe Morrell, Lee Brown; Marcus Harness, John Marquis (George Hirst 70). Subs not used: Alex Bass, Gassan Ahadme, Michael Jacobs, Miguel Azeez.

Goals: Smith 29, 55, Wood 60, Wiles 63 (Rotherham); Harness 49 (Portsmouth).

Referee: Anthony Backhouse (Cumbria).

Attendance: 9,684 (1,242).