S.J.
I think the other poster is right that he may just be ready to transition into one nap. :)
Also, sometimes they just need extra huggies after nap time. My youngest is now three and needs 20-30 minutes after nap to just lounge around and be the baby. I think they need more of that time at the end of the day.
Transitioning to one nap is fun! {sarcasm} Some kids may do it very easily, but for mine it seemed to be slow going. Gradually pushing back the first nap and decreasing the second. But worth it for a happy kid. :)