The Congolese and Argentine midfielders are pivotal to breaking up attacks and maintaining possession, writes Richard Jolly.
Bargain buys Mulumbu and Yacob are WBA's protective shields
Five years ago, Anfield reverberated to the sound of a song proclaiming that, with Xabi Alonso, Momo Sissoko, Steven Gerrard and Javier Mascherano, Liverpool had the best midfield in the world.
As often happens with football chants, it was borrowed and customised. As West Bromwich Albion cruised to the Championship title, the same claim was made about their quartet of Zoltan Gera, Filipe Teixeira, Robert Koren and Jonathan Greening (or, for the purposes of rhyme, "Jono").
An enterprising and entertaining group they were, too, the best in the second flight if not the planet. Now, however, Albion have a more credible claim to midfield supremacy.
As protectors of a defence, Youssouf Mulumbu and Claudio Yacob may be unrivalled in England. What can be said with some certainty is that, pound-for-pound, they are the best midfield pair around.
And that is because, with remarkable recruitment, West Brom have acquired the duo for a combined £150,000 (Dh884,000), the fee they paid Paris Saint-Germain for the Congolese in 2009. Yacob arrived on a free transfer from Racing in his native Argentina in the summer.
Born in Santa Fe, the province that also produced Lionel Messi, the Buenos Aires club were his only previous employers, but he also had international experience. He had played for the Argentina team which, captained by Sergio Aguero, won the Under 20 World Cup in 2007 and was capped three times for the senior side.
But, though linked with Arsenal earlier this year and Manchester United more recently, the competition West Brom actually faced for his signature came from the Brazilian side Botafogo. It was part scouting, part detective work that confirmed the Argentine was worth buying: West Brom's former sporting director Dan Ashworth scaled a fence to watch Yacob train.
While Ashworth was acquiring an in-depth knowledge of his target, others knew rather less. The goalkeeper Ben Foster said he had never heard of Yacob. Even the coach Steve Clarke had never seen him play.
Yet when the West Brom faithful first watched him, they were impressed. Yacob was named man of the match in the opening day 3-0 win over Liverpool when he subdued Gerrard.
A dozen games into the season, with West Brom's defensive record second only to Manchester City's, with Yacob's pass-completion rate hovering around 90 per cent and with him in the group of players who have made the most tackles in the Premier League, his strengths have quickly become apparent.
"He's an Argentinian No 5, who breaks up play and keeps the ball for his team," said Clarke, referring to the Argentine tradition of tough technicians who can anchor the midfield. The centre-back Jonas Olsson, one of the beneficiaries of Yacob's services as a shield, had one in mind.
"I can definitely see the comparisons with Mascherano," said the Swede. "He's such a physical player. For me, he is one of the best defensive midfielders in the world. When you have someone like him and Youssouf Mulumbu sitting in front of you, it is a big help."
But if Yacob has gained the nickname of "Silent Assassin" for the unobtrusive way in which he goes about his business, Mulumbu tends to be more prominent.
The 2010/11 season, which brought seven goals and two red cards, is an indication of his all-action style. Born in Kinshasa, the France Under 21 player opted to play for his native country at international football.
"In England, I'm Mr Everybody," he said in 2011. "People can see me shopping. But in Congo, I need a bodyguard when I go out … I'm the Congolese Beckham!"
His development was aided by his time in France. Mulumbu both understudied and idolised Claude Makelele at PSG and, though more athletic than his hero, he can perform the same role. He, too, was identified by Ashworth, and while then manager Tony Mowbray was keen to push through Mulumbu's signing his successors have reaped the rewards.
In the process, the West Brom midfield, so adventurous a few years ago, has been rebranded. It is now a department of two halves: the stoppers, in Mulumbu and Yacob, and the potential scorers, such as Gera, James Morrison and Peter Odemwingie.
It is the nature of the defensive midfielder's job that others get the headlines and while Albion are the interlopers in the top four, they have generated plenty of good publicity for Clarke, the rookie manager outperforming many a veteran, and Shane Long, the indefatigable lone striker, plus the creative contingent just behind him.
But in Yacob and Mulumbu, West Brom's answers to Mascherano and Makelele, the basis of their success can be traced to the heart of the midfield. To the men who win the ball back and rarely give it away.
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