Former Netherlands and Barcelona defender Ronald Koeman is primed to replace Quique Setien as Barcelona's head coach.After Setien was sacked on Monday evening, all renowned Spanish news outlets such as Sport, AS and Marca have pointed towards Koeman to be appointed as the next Barcelona manager, which is one of football's worst kept secrets at the moment.❗ Quique Setién no longer first team coach.The new coach will be announced in the coming days as part of a wide ranging restructuring of the first team.— FC Barcelona (@FCBarcelona) August 17, 2020In an official announcement, Barcelona hinted towards a major overhaul in their first team.While some players are indispensable, Koeman is expected to have his say in rebuilding the squad. Despite their recent form and fringe status at the club, five players could still make an impact at Barcelona under Koeman. Let us have a look at them.Five Barcelona players who could make an impact under Ronald Koeman:#5: Junior FirpoReal Betis Balompie vs FC Barcelona - La LigaFormer Real Betis full-back Junior Firpo was lauded as one of the biggest prospects in Spain when he made his €18 million (plus €12 million in add-ons) move to the Catalan capital.However, his progress was halted by a lack of game-time and Barcelona's tactical consistency. Koeman, though, who has a knack of nurturing young talent, could come to the rescue of the young defender.#4: Sergi RobertoFC Barcelona vs Club Atletico de Madrid - Supercopa de Espana: Semi-FinalSergi Roberto, one of the heroes of Barcelona's famous 6-1 comeback win against PSG in the Champions League in 2016, hasn't bloomed into a key player at the club since that historic night.90 min+2: GOAL GOAL GOAL GOAL GOAL! The comeback is complete! 👏👏👏👏@SergiRoberto10 FCB 6-1 PSG (agg. 6-5) #FCBPSG #FCBLive #ForçaBarça! 💪🔵🔴 pic.twitter.com/lcrCK8NmA3— FC Barcelona (@FCBarcelona) March 8, 2017His versatility can sometimes be counter-productive to him and the club. However, Koeman could provide stability to the Spain international by having him as a midfielder.