The 22-year-old opened the scoring at Stamford Bridge over the weekend, finding the net just 15 minutes into the game before Conor Gallagher and Noni Madueke extended their advantage to 3-0 before the interval.
Nicolas Jackson scored twice in the second half, securing an important victory for the Blues, who are still battling to secure European qualification.
Despite a challenging season for Chelsea, Palmer has emerged as a standout performer and has consistently delivered goals and assists for Mauricio Pochettino's side this term.
Palmer matches longstanding debut season record for ChelseaPalmer's goal against the Hammers was his 21st in the Premier League this season, and with nine assists to his name, he has now become just the second player in Chelsea's history to achieve 30 goal contributions in their debut season for the club.
The first player to achieve this feat was Hasselbaink, who recorded 23 goals and seven assists during the 2000-01 campaign.
With three games remaining in the season, Palmer is set to surpass this longstanding record.
In addition, the 22-year-old has now equaled the records of two of Chelsea's greatest goal-scorers of the modern era, Frank Lampard and Didier Drogba.
Lampard and Drogba share the record for the most Premier League home goals in a single season for Chelsea, with 16 each. Drogba was the first to achieve the feat during the 2006-07 season, followed by Lampard in 2009-10.
Palmer eyeing up one more record on final day of the seasonWhile Palmer's strike against West Ham brought him level with the Chelsea legends' records, he now has only the
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