James Wildman, managing director and vice-president of sales, UK and Ireland, who undertook the restructure, told Media Week the appointments marked a "departure" for the company and would help its UK operation work better with brands to "maximise opportunities, which having deep and rich content allows".
Yahoo has hired Ben Murphy, former online and mobile controller at BSkyB, and Dan Durling, former account director at Global Radio, to the newly created roles of account group leaders. They are working alongside current account group leader, Matt White and report to Steve Brown, sales director at Yahoo UK.
Yahoo is also boosting its direct response (DR) operation and has hired Experian's Gareth Shaw as its first senior DR specialist.
Wildman said: "With the rise of trading desks and some interesting developments within the DR marketplace, we are putting investment into this specialist area."
Sam Coleman, former communications director at MEC, is joining the company as its new group planner. Coleman and Shaw both report into Brown.
Another key hire for the company is within its Studio proposition, which was launched as part of the restructure last year, with the aim of delivering more creative opportunities for advertisers.
It has appointed Russ Williams, former head of digital and business development at production company Wise Buddha, to the role of studio production lead, which is the first project manager role within the 17-strong Studio team.
Williams reports to Krane Jeffery, head of Yahoo Studio.
The hires take the team to around 150 people, with more appointments expected over the next few months. They started working at Yahoo this month.
There have been around 10 redundancies since the new structure was unveiled in August.
Yahoo's sites, which include news, sports and gossip site OMG!, received 25.8 million unique visitors in the UK in December 2011, according to comScore data.
However, the company however faces tough competition in the online ad sales market from the likes of Google and Facebook.
Wildman said that Yahoo was responding to this challenge by providing advertisers with more complex and creative ad solutions, which are editorially aligned.
He said: "We are competing with strong global competitors like Google and Facebook, who are fabulous in their own right, but they don't have the media credentials that we have in spades."
He said Studio was gaining traction with agencies and had already achieved some significant deals, worth £600,000 upwards, with brands including Nokia, British Gas and Kellogg.
"We are working in a soft market and everybody is challenged. If you take brand equity and look at how the product is performing, where we are taking it and the work we are doing from a sales perspective, we are sat very positively."
According to the company's latest financial results revenue, excluding commissions paid to partners, slipped 4% year on year to $1.17bn (£750m) for the fourth quarter of 2011.
Revenues in EMEA, however, were up, from $106m for the fourth quarter of 2010, to $110m a year later.
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