AS a native of the Spanish city of Pamplona, Newcastle United midfielder Mikel Merino knows all about taking on a challenge.

Every summer, Pamplona stages the nine-day San Fermin festival, which has as its centrepiece the ‘Encierro’ or ‘Running of the bulls’. Six bulls are released into the warren-like streets, with thousands running alongside them as they tear through the city.

“It’s dangerous, but it’s a normal thing there,” said Merino. “During all the history there, it has always happened, and it will continue. Nobody thinks about the dangers – it’s just normal there.”

If a life-or-death stampede is the 21-year-old’s idea of ‘normal’, perhaps it should not be a surprise that he has handled the hurly-burly of midfield life in the Premier League so effortlessly. If you’re used to a tonne-and-a-half of bull running at you, you’re unlikely to be fazed by a nudge from Darren Fletcher.

Even so, of all the pleasant surprises that have accompanied Newcastle’s rise to fourth position in the table, Merino’s emergence has been one of the most unexpected of the lot.

His loan move from Borussia Dortmund was somewhat lost amid the acrimony and angst of the final few weeks of the transfer window, with Rafael Benitez’s desire to sign the likes of Lucas Leiva or Fabian Delph leading many observers to conclude that the Spanish Under-21 international was simply the first person on Newcastle’s wanted list who was available for a cut-price fee.

In fact, Benitez had been tracking him for a number of seasons and would have tried to sign him even if he had been able to land another of his midfield targets, but Merino’s reputation was hardly enhanced when his debut appearance at Huddersfield was branded “weak” and “a joke” by Sky Sports pundit Graeme Souness. Three games later, and if he had an ounce of humility, the former Magpies manager would be publicly eating his words.

Merino ran the game as Newcastle claimed their first win of the season against West Ham, and was the Man of the Match in the 1-0 win over Swansea, comprehensively out-performing the much-heralded Renato Sanches.

Last weekend, he was catching the eye again as his mastery of the midfield area helped his side claim a third successive victory against Stoke. Moving into the Premier League at the age of just 21 is supposed to be one of the hardest tasks in football, especially when you’re coming off the back of a season that saw you make just nine senior appearances for Borussia Dortmund. To Merino, however, it has been an effortless transition.

“I look like I’ve been in English football for ten years? No, I think ten years is too much,” laughed Merino, whose father, Angel, was a professional footballer with Osasuna and Celta Vigo. “I look comfortable playing football, but that’s not only in the Premier League, it’s because it’s what I like, what I love.

“I’ve been doing it since I was seven years old, and for me it is my love. It doesn’t matter if we are playing at a higher intensity now, I just have to adapt to it.”

The whole of the Newcastle squad are adapting to life in the Premier League following last season’s Championship title success, with a run of three victories having swept away the concerns that accompanied defeats to Tottenham and Huddersfield at the start of the campaign.

Benitez’s side have been solid at the back, conceding just two goals in their last four matches, and for all that he might be comfortable in possession, Merino’s work rate, anticipatory skills and willingness to throw himself into a tackle have been major factors in his side’s defensive strength.

Unlike some central midfielders, though, he is also keen to get on the front foot whenever possible, and while he might have got his chance when Jonjo Shelvey was banned, it is telling that he has remained in the team despite Shelvey having completed his suspension.

“I am sure me and Jonjo can play together,” he said. “All the midfielders can play together, we have a connection and it doesn’t matter who plays because whoever it is will do really well.

“That is one of the things that is really important in football - if you trust in your team-mates, then it doesn't matter who plays because you can make it really clear whose job is which and adapt to it.”

While Merino has initially joined on loan for a one-off fee of around £2.7m, Newcastle have agreed a cast-iron clause that will enable them to sign him permanently for an additional £6.5m next summer. Five games into his Tyneside career, and it already looks an extremely astute piece of business.

“I would have taken this first month if it had been offered to me when I signed,” said Merino. “It would have been perfect if we’d won all the matches, but the way we are playing, the way the team thinks about playing football, the penetration and concentration - all these things are perfect at the moment.

“I'm really, really happy to be here, enjoying every training (session) and every match. It is enjoyable to play matches here, and of course it is even better to do it winning.

“We just have to keep going, this doesn’t stop. We have to keep playing with this effort, this rhythm, and just doing our work - and keep winning if we can.”