Marko Grujic
Marko Grujic joined Liverpool in January but was immediately loaned back to Red Star BelgradeGetty Images

Jurgen Klopp has received a boost ahead of the new season, with Liverpool announcing a work permit for Marko Grujic. The 20-year-old will begin pre-season alongside the rest of his teammates on 9 July, and will be available for selection in the Premier League opener against Arsenal on 13 August.

The Serbian U21 international was the first signing of the Klopp era at Anfield, with the Merseysiders paying Red Star Belgrade £5.1m ($6.7m) for his services last January. However, the young midfielder was loaned back to his former club for the remainder of the campaign, before he could have the chance to establish himself at Liverpool.

The Reds needed to convince the FA to issue a work permit, as Grujic did not qualify for it automatically under current regulations.

"Marko Grujic can officially begin his Liverpool career after successfully being granted a work permit today," the clubconfirmed.

"The 20-year-old joined the Reds from Red Star Belgrade in January, but returned to the Serbian club on loan for the second half of the 2015-16 campaign. Grujic began pre-season training at Melwood on Saturday and following the successful conclusion of the work permit process will now be eligible to play for Liverpool‎. The midfielder will wear squad No. 16."

Klopp has bolstered his squad in the current mercato with the additions of former Southampton winger Sadio Mane, centre-back Joel Matip and goalkeeper Loris Karius. Meanwhile, the club are yet to make an official decision on the future of players who were on loan last season such as Mario Balotelli, Luis Alberto and Lazar Markovic.