Long-time Klopp assistant Zeljko Buvac recieves work permit, joins Liverpool

New Liverpool boss Jurgen Klopp officially welcomed his long-time assistant coach Zeljko Buvac to the club on Wednesday, after an issue with getting a work permit delayed his arrival.

The two coaches have a professional relationship and friendship that has spanned more than 20 years, and have been on the sidelines together for over a decade.

After jumping between teams as a player, Buvac joined Klopp at Mainz in 1992. They were teammates for just three years, but it was all the time they needed to start what has become a dynamic coaching duo.

When Klopp, who spent his entire playing career at Mainz, was made coach of the German club in 2001, he called on Buvac to assist him. They stayed there until 2008 and then moved to Borussia Dortmund, where the two shared a successful stint over the following seven seasons.

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Klopp has often described his No. 2 as the "brains" of the coaching staff. Buvac helped established the kind of high-flying football made so famous at Dortmund: The constant pressing, the unrelenting pace, and most importantly, all the goals scored.

Dortmund won the Bundesliga twice under Buvac and Klopp's watch, taking a previously mid-table club to the title within just a couple of years.

That style of playing is beginning to take hold at Liverpool.

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In just the first week of training under Klopp, midfielder Lucas Leiva has already noticed an increase in tempo.

"It has been very good, very positive and hopefully it will keep going like that," Leiva told Liverpool's official website. "He seems to be very passionate - he likes to put in everything that he has and he asks the players for the same.

"Be very intense, be aggressive with yourself, is what he has been saying. Always try to be better, always give 10 metres more, because that will be the key to success. That is what he has been saying to us in the last couple of days."

Liverpool plays away at Tottenham on Saturday in the club's first official match under Klopp.