Nottingham Forest's manager Vitor Pereira is already at risk of being sacked if the club loses star players and endures a slow start to next season. The 57-year-old was appointed following Sean Dyche's dismissal in February and led his side to safety in the Premier League with an eventual 16th-placed finish. However, they are at risk of losing a number of the club's most important players this summer, which could set them up for trouble when next season begins. Former Man United chief scout Mick Brown told Football Insider that Forest are more likely to sack Pereira if he loses Elliot Anderson and Morgan Gibbs-White. A strong start to next season will be crucial to the manager's future, but a long transfer window is looming and is likely to have a major impact on his chances. Nottingham Forest's owner Evangelos Marinakis could 'upset the apple cart' despite the club's plans to back Pereira. Marinakis is notoriously trigger-happy when it comes to managers, and another season threatened by relegation could force his hand. Vitor Pereira will be under pressure, very much so, according to Brown. Forest are one of those clubs you look at, and you can see they're capable of playing at a certain level, because they have some very talented players there. But if they lose some of those players, like Elliot Anderson, Gibbs-White, Murillo, then it's going to be a massive blow, because they were battling relegation even with them. The problem is, the blame gets pointed at the manager, and then he finds himself in trouble when realistically the problems have been caused by losing key players. It looks like Anderson will go to Man City, there is a lot of interest in the other two, and if Forest can't keep hold of them, they're in danger of having a slow start to next season. That will then lead to frustrations, and the owner has shown over the last year what he is likely to do when they're threatened by relegation. Doubts over Nottingham Forest's preparations for next season have already begun to creep in, just weeks after they secured survival in the Premier League. A difficult transfer window is now looming, with players including Anderson, Gibbs-White and Murillo all attracting interest from high-profile clubs. Brown told Football Insider on 8 June that Nottingham Forest are determined to keep Gibbs-White as they have no plans to lose more than one key player. Anderson looks to be edging towards a move to Man City despite a formal bid having been rejected, and his departure will strengthen Forest's resolve over his teammate. Should they prove unable to keep their best players at the City Ground, a downturn in performances could have a major impact on the boss' position. Nottingham Forest's fans will be anxiously waiting to see what the future holds for their club. The transfer window is always a time of uncertainty, but for Forest, it could be a make-or-break summer. With the club's Premier League status hanging in the balance, the decisions made in the coming weeks will be crucial. Vitor Pereira's future as manager is far from secure, and the loss of key players could be the final straw. The club's owners will be under pressure to make the right decisions, and the fans will be hoping that they can keep their best players and build on last season's survival.