Chelsea say the number of penalties they have been awarded in the Premier League this season seems "abnormally low" compared to other years.
An article on the club's website points out Jose Mourinho's side have been awarded two so far, while Arsenal and Manchester City have had seven each.
Mourinho was fined in January for claims of a campaign to influence refereeing decisions against Chelsea.
The article, titled 'Penalty Puzzle', gives the number of penalties Chelsea have received in the Premier League in the last six seasons.
Last season they were awarded seven.
"So this season's tally of two unquestionably bucks the recent trend, yet our position as clear league leaders and second-highest scorers suggests we can't be labelled anything other than an attacking side, spending plenty of time in the opposition box," the article says.
|Chelsea paying the penalty?|
|Season||Number of penalties||Premier League position|
"Of course, it could be that when teams have played the league leaders they have been particularly careful inside their own area. We all have plenty of recollections suggesting this is not the case, however."
The article also highlights incidents during the season where it says Chelsea should have been awarded penalties.
These include: A challenge on Branislav Ivanovic in last Sunday's 1-1 draw with Southampton.
A challenge on Cesc Fabregas, who was booked, in the return game at St Mary's, which also ended 1-1.
A challenge on Diego Costa at Burnley and a handball appeal against the Clarets in a 1-1 draw at Stamford Bridge last month.
A claim for handball at Tottenham in a 5-3 defeat in January.
Suggested fouls on Ivanovic and John Terry in a 1-1 draw at Manchester United last October.