Fortunately, it was during lunch! I blame the soccer on the TV at The Local.
So I kind of relaxed into it and didn't struggle against the oncoming nap attack. I was waiting for my food anyway and was tucked into a nice corner with a lovely sunbeam just peeking in the window. I awoke when my food (a nice salad with salmon, very light on the carbohydrates to avoid a carbo-crash later in the day) arrived and ate a fairly leisurely lunch.
The rest of the day passed without any problem and I was able to get quite a bit done in the afternoon. Tomorrow, however: Ritalin!