New Barcelona coach Ronald Koeman faces a series of decisions over his squad as he takes over the reins from predecessor Quique Setien.

With some of the club's biggest names nearing the twilight of their careers, Koeman must decide whether to stick or twist in the process of overhauling the playing staff at the Nou Camp, where president Josep Maria Bartomeu has insisted star man Lionel Messi remains a key part of the plan.

Here, the PA news agency takes a look at some of the men who may come under the spotlight.

Luis Suarez

Uruguay international Suarez remains a potent weapon in the Barca armoury having scored 21 goals last season to take his tally for the club to 198 since his £75million arrival from Liverpool in July 2014. However, he will celebrate his 34th birthday in January and the ravages of time will eventually start to take their toll on a man who has toiled tirelessly at the business end since he was a teenager.

Gerard Pique

In a frank assessment of Barca's 8-2 Champions League quarter-final drubbing at the hands of Bayern Munich, central defender Pique admitted that heads would have to roll and that his could be one of them. He has spent the last 12 years at the Nou Camp following his return to his boyhood club from Manchester United, but he too will celebrate his 34th birthday early next year and will know that the end of his distinguished Barca career, which has yielded 20 trophies, is approaching sooner rather than later.

Sergio Busquets

One-club man Busquets established himself at Barca as a member of a famous midfield triumvirate along with Xavi and Andres Iniesta which was the envy of Europe. However, time eventually caught up with even the great Xavi and Iniesta and 32-year-old Busquets, who has almost 500 appearances to his name, will at some point in the not to distant future inevitably follow in their wake.

Ivan Rakitic

Compared with Busquets, Croatia international Rakitic is a relative novice at the Nou Camp having arrived from Sevilla just six years ago. He has done well to help offset the loss of Xavi in particular, but life in the midfield engine room becomes increasingly testing and Koeman will need fresh legs eventually as he looks beyond what may remain of the career of a man who turns 33 in March.

Arturo Vidal

Vidal finds himself in a similar boat to Busquets and Rakitic, although, as the senior member of the trio, the combative Chile international may have the most to prove to his new boss. He has spent the last two seasons in Catalonia following his move from Bayern Munich, although 45 of the 33-year-old's 96 appearances to date have come from the bench.