Chelsea currently sit on top of the Premier League after a blistering start to the season that has seen them secure 25 points from 10 games. The Blues have faced Arsenal, Tottenham Hotspur, Manchester City and Liverpool, losing just once during that time.Manager Thomas Tuchel has managed to put his very large squad to good use, but some players have failed to consistently impress when called upon.Some Chelsea players have struggled despite strong start from the teamHere is a list of some of Chelsea's stars who have failed to live up to their potential on a regular basis at the club. Despite receiving numerous chances to prove themselves to the manager, these players have failed to make a great impression consistently.Without further delay, let's delve straight into it:#5 Timo WernerChelsea v Southampton - Premier LeagueKnown during his time in the Bundesliga for his blistering pace and excellent finishing, Timo Werner has only shown glimpses of what he can do since moving to Chelsea. Werner joined Chelsea for a reported fee of £54 million from RB Leipzig in the summer of 2020.The striker has hardly reached the heights he hit during his time at Leipzig and has struggled for goals and confidence since his arrival in west London.CFC-Blues ⭐️⭐️@CFCBlues_comOn This Day last year, Ziyech, Zouma and Werner scored in our 3-0 win against Burnley at Turf Moor 👏 #CFC 08:03 AM · Oct 31, 202189451On This Day last year, Ziyech, Zouma and Werner scored in our 3-0 win against Burnley at Turf Moor 👏 #CFC https://t.co/JCwcpdOW1nWhile he has failed to deliver in front of goal, Werner continues to work hard with his movement and pressing for Chelsea. As such, the 25-year-old is only fifth on this list. Despite concerns surrounding his form, Werner managed 12 goals and registered 15 assists in all competitions during his debut season where he also won the Champions League with the club.However, the Germany international has scored just twice in 10 appearances so far this season. If Werner is to have a successful career at Stamford Bridge, he must stop blowing hot and cold too often.#4 Marcos AlonsoMalmo FF v Chelsea FC: Group H - UEFA Champions LeagueSpanish left-sided defender Marcos Alonso has distinguished himself as one of the best left-wing backs in Europe with his dazzling displays on his day. The problem with Alonso is that his days are usually few and far between.The former Bolton Wanderers man started the 2021-22 season in supreme fashion and even scored a brilliant free-kick against Crystal Palace on the opening day of the season. His early-season form saw him keep Ben Chilwell on the bench and also earned him a recall to the Spanish national team.Absolute Chelsea@AbsoluteChelsea🌟 Trevoh Chalobah, Marcos Alonso, Saul Niguez and Kai Havertz have all been included in the @Carabao_Cup Team of the Round, powered by @WhoScored.09:43 AM · Oct 28, 20212680188🌟 Trevoh Chalobah, Marcos Alonso, Saul Niguez and Kai Havertz have all been included in the @Carabao_Cup Team of the Round, powered by @WhoScored. https://t.co/009fYSVq6wHis form since then has dipped worryingly, as it did with alarming regularity under previous managers at the club. His loss of form coincided with Chilwell returning to a purple patch.As a result, Alonso has hardly had a look-in in recent fixtures for Chelsea. He also failed to impress when playing from the start against Malmo in the Champions League.