There was a time when Mark Hughes’s prowess in the transfer market and Benni McCarthy’s ability as a finisher went equally unquestioned. If the Welshman’s recent recruits during his time at Manchester City have drawn damning verdicts, Blackburn’s South African striker provided a reminder of his acumen during his time at Ewood Park.

Signed for £2.5million, McCarthy scored 18 Premier League goals in his debut season in England. That this was his first of the current campaign indicates the recent decline in his fortunes. That Rovers have not won since early November illustrates that they have fared no better in the absence of Hughes, who led them to three top-10 finishes. Hugo Rodallega deprived them of two points with a deserved equaliser.

The Colombian struck when he met Maynor Figueroa’s cross with an emphatic header. A similar display of composure in front of goal had been provided by McCarthy. He was denied a winner when Chris Kirkland blocked his overhead kick. The striker had deftly volleyed past Kirkland in more conventional fashion after Ryan Nelsen had headed Keith Andrews’s free-kick into his path.

Such an assured finish was at odds with the action that preceded it. In a farcical first few minutes, the sides almost traded own goals. Titus Bramble applied a touch to McCarthy’s teasing low cross which, while denying Franco di Santo a tap-in, almost produced the same outcome, as the Wigan defender came perilously close to scoring an own goal.

Then Bramble’s chip forward was misjudged by Christopher Samba, whose backward header made Paul Robinson first scurry back and then dive to claw the ball off the line.

Indeed, an afternoon of mishaps continued after McCarthy gave Blackburn the lead. David ‘Junior’ Hoilett may well have doubled their advantage had his shot not been deflected wide by the back of his unwitting team-mate Andrews.

It came in a half where Blackburn were the superior side. Wigan were in the ascendant afterwards and Rodallega earned their reward.

Premier LeagueWigan AthleticBlackburn Roversguardian.co.uk

Five defeats from five away matches this season has placed a huge emphasis on Blackburn’s home form and for 45 minutes it deserted them entirely here. Sam Allardyce rang the changes at half-time and two second-half goals from the substitute Jason Roberts and one from the captain, Ryan Nelsen, cancelled out Jamie O’Hara’s opener and put Blackburn six points clear of last-placed Portsmouth.

“I might just have earned my money this week,” said Allardyce after his decision to introduce Roberts and Benni McCarthy in place of his wingers, El‑Hadji Diouf and Morten Gamst Pedersen. “I’m not usually that radical at half-time, but that was our worst first-half performance this season.” Portsmouth were untroubled by the home side’s largely ineffective and unimaginative attacks in that opening period and enjoyed the best of the play, with O’Hara and Kevin-Prince Boateng quick to get forward in support of Frédéric Piquionne and Aruna Dindane.

This hastily formed front pairing seem to be developing a nice understanding and it was Dindane who can claim the assist for O’Hara’s opener. The Ivorian squared the ball to the midfielder and when no defender closed him down he let rip with a 30-yard daisy-cutter that flew into Paul Robinson’s bottom left corner.

O’Hara was booked 10 minutes before the break following a tussle with Pascal Chimbonda, who was slightly fortunate to escape with a booking, too, after appearing to lash out at the Portsmouth man with his right hand.

Having seen his side outplayed, Allardyce decided to mirror Portsmouth and switch to a diamond formation and the alteration paid off within eight minutes – Roberts was perfectly positioned on the edge of the six-yard box to swivel and stab the ball beyond David James after Nelsen had climbed highest to nod down a Dunn corner.

Blackburn were ahead with just over a quarter of an hour to play when another Dunn corner from the left was again met by Nelsen – this time the Blackburn captain finished the job himself, slamming a powerful header beyond James, who elected to stay on his line.

Roberts sealed the points with his second of a highly effective 45-minute appearance, when he swept home McCarthy’s marvellous low cross after the South African had combined with Dunn down the left.

Paul Hart did not blame defeat on Allardyce’s tactical nous, preferring a more typical excuse for those vanquished at Ewood: “I don’t think we have been done by any great genius. We were simply done by set pieces,” he said. “If you don’t defend set pieces against Blackburn, you are going to be in trouble and that is what happened.”

Premier LeagueBlackburn RoversPortsmouthMikey Staffordguardian.co.uk