Credit: Maury Phillips / Stringer / Getty Images Photo: Host Nathan Fillion Speaks at the 2013 Writers Guild Awards on Feb. 17, 2013

For the second time in as many months, Nathan Fillion (Richard Castle) was a no-show on the Los Angeles set of the his ABC drama, Castle. While his absence earlier this summer was because of a disagreement with the production company after he requested a four-day (Monday-Thursday) work week, he had a much more valid reason for not showing up to work today, September 13.

According to Deadline, the 42-year-old actor called in sick because of a “sore back he is seeing a chiropractor for.” Nathan’s back problems are described as “chronic,” and a source says it’s not unusual for him to seek medical attention if and when his back is aggravated.

Although the cast and crew were said to be worried that his most recent absence from set was once again related to the show’s schedule, sources claim his back issues are solely to blame this time around. Luckily, production was able to schedule filming around Nathan for the day. He is expected to be back on set on Monday, September 16.

Are you surprised that Nathan has missed another day of work on Castle Season 6, or do you sympathize with his back problems? Tell us your thoughts below!

Source: Deadline