Viktor Gyokeres has been told that he is "too heavy", with the Arsenal striker was advised to lose weight to achieve Premier League success. The Gunners' bold summer gamble on the Sweden international was meant to herald a new era at the Emirates Stadium, but his first weeks in north London have been dominated by concerns rather than celebration. He was signed for a total fee of £63.5 million from Sporting CP, but questions have been raised over his physical readiness for English football's unforgiving pace.Gyokeres arrived at Arsenal with the reputation of a late bloomer. Though he spent four years contracted to Brighton between 2017 and 2021, he never played a single Premier League minute, instead reviving his career through two prolific seasons at Coventry before conquering Portugal with Sporting. Feeling he had outgrown Lisbon, the striker pushed to complete his move to the Emirates. But the drawn-out transfer had left him behind in his conditioning. His debut came under sweltering conditions in Hong Kong during a 1-0 defeat to Tottenham, a match in which he appeared short of rhythm and sharpness. Social media was quick to point out that the new signing appeared "a little heavy", prompting early whispers over whether he had reported for duty in peak physical condition. Just as Gyokeres seemed to be settling into his new surroundings, disaster struck. During Arsenal’s 2-0 win over Burnley at Turf Moor, a match in which he opened the scoring before Declan Rice added the second, the Swede signalled discomfort and was withdrawn at half-time. Arteta’s post-match tone was measured but clearly troubled. "I am concerned because he hasn't had many muscular issues and he needed to leave the pitch and he was feeling something," he told reporters. "That's obviously never a good sign, especially for a player that is very, very explosive. So we are digging in a little bit more to understand where we are in terms of the injury and we'll announce the moment we know."Former Arsenal star Stefan Schwarz believes the striker’s struggles are rooted not only in physical shortcomings but also in mental and tactical adaptation."I believe with Viktor Gyokeres, he's not fully fit yet," he told in an interview with Hajper. "As well with the new system, new manager, and new teammates, it takes time to develop the understanding. It's not just the physical part of it, it's the mental part as well. Mental tiredness may be from adapting to a new club, new expectations, and higher expectations from supporters around the whole world. But it's a good partnership (Gyokeres and Arsenal). And hopefully it will benefit Sweden for sure and Graham Potter."Despite the criticism, Schwarz remains optimistic that Arsenal is the right environment for the striker to flourish."He's in a strong team. Arsenal has been fighting for the big titles, so maybe he can help the team to take this big step. But, of course, everyone is a piece of the jigsaw puzzle," he added."So everyone is important, but of course, he has a big presence. He's a strong, physical guy, and a good finisher with both feet. However, he needs to get his fitness up. I think he's in the right team with Mikel Arteta and the players around him. It's a fantastic squad. The quality shown by the players on the bench and the options that Arsenal have means that Gyokeres won't play all the games because I think they have a lot of good options to make tactical decisions from time to time based on the opponent or the result during the games."Schwarz did not shy away from the blunt assessment that Gyokeres needs to shed a few kilos to be successful in the Premier League. "Sometimes the dog who barks loudest is not always the strongest," he said. "I think it's just the players in the Premier League. They are more powerful players, faster players. The strikers will always be counted on for the goals that they are scoring. Hopefully, he'll start to create and score goals, have a good run, get that real boost, and get a bit lighter because he's a heavy player. I think that would help."He didn't have a proper pre-season, and you need to play the games. You have those six weeks to interact with your colleagues, to understand the movement. When the midfielder makes the pass, you just have to look in their eyes, you know where they'll pass it. That's a relationship that takes a bit of time, and football is about fine margins. Look at Dennis Bergkamp, he was the best at that. He will learn and score a lot of goals, and that will benefit Arsenal."Arsenal’s first match after the international break is no gentle reintroduction as it happens to be a north London derby with Tottenham at the Emirates on November 23. The club hopes that Gyokeres’ injury is not severe enough to rule him out of the biggest league fixture of their season so far. He may not be the only player racing the clock. Arsenal are also monitoring the recoveries of Noni Madueke, Kai Havertz and captain Martin Odegaard, all of whom could return in time for the showdown with Spurs.