In a manga I am reading, I found this sentence:


I understand its meaning from context:

I also sleep around 9 in the morning these days.

But I don't get why there is の between 寝る and 朝. I would like to see word to word translation. Is it a contraction of


or something like that?

Source: (働かない二人) http://yamakamu.com/archives/4077130.html