The two London outfits sit in eighth and ninth position in the Premier League standings respectively after a season of inconsistency.
Although Chelsea have spent much of the campaign behind West Ham in the table, Thursday's 2-0 victory over Tottenham Hotspur moved them two points clear of the Hammers.
While each team can benefit from Manchester United and Newcastle United — the teams in sixth and seventh — still having to play each other before the end of the season, a defeat for either side on Sunday could prove pivotal in the race for the top seven.
Between them, the teams have only recorded one win in their last three top-flight fixtures, highlighting that neither club enter this contest in particularly convincing form.
Nevertheless, the statistics suggest the most likely outcome is a high-scoring Chelsea victory, one which they would gratefully accept despite their desire to record back-to-back clean sheets in the Premier League for the first time in 14 months.
Why supporters should expect goalsThere is nothing particularly special about their respective attacking records. Chelsea and West Ham possess the seventh and eighth best returns in the final third.
However, West Ham possess the fourth-worst defensive record in the division, conceding 65 times in 35 games, while Chelsea have the eighth-worst with 59 goals being shipped in 34 outings.
That is a club record for Chelsea and they would become just the second team in Premier League history to score and concede at least 60 goals if they do not keep a clean sheet this weekend.
Chelsea also head into this encounter
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