This was a good lesson.
Day before the race: I did an anti-taper day, the day before the race i ran about 9 miles easy and then played soccer the evening before the race; so overall i ran about 5 soccer miles in addition to the easy run.
Race day: I started the race sub 7 mile pace the first 2 miles;too fast! then i broke down and kind of made it to the finish; in addition my GI system was also irritated; while crossing the finish line i had the strongest urge of throwing up however fortunately i did not need it to do.
I wanted to run this race that way w/o any taper to mimic a marathon like situation of mile 16 or so; this definitely seemed to work; i felt really bad the whole race; and i was barely only able to run marathon pace; but not 10K pace; it felt like treshold pace or V-MAX; the conditions were very humid; too warm all of the sudden as well;
I think a long run the day before is okay; but an all out soccer game at the evening i cannot recommend. will take it easy next time in terms of soccer; nevertheless i still was able to PR from my last 10k in January/2013.