Lol lol - sorry - I realized after I responded that my translation was pretty much the same as yours. That said, my brother used to play football one on one when there were only a few guys willing to come out in the rain for no money (my brother's a serious die-hard)
(soccer link) http://wehewehe.org/gsdl2.85/cgi-bin/hdict?a=q&r=1&hs=1&m=-1&o=-1&e=d-11000-00---off-0hdict--00-1----0-10-0---0---0direct-10-ED--4-------0-1lpm--11-en-Zz-1---Zz-1-home-kama--00-3-1-00-0--4----0-0-11-00-0utfZz-8-00&q=soccer&j=pm&af=1&fqf=ED
(pōwāwae link) Pōwāwae. ~ ball. Kinipōpō pōwāwae.
[MK]1 n Soccer. Sh. Kinipōpō + wāwae. Kinipōpō pōwāwae. Soccer ball.
I answered "The football game is yesterday" simply because there was no "Ua" to indicate past tense. I know "nehinēi" is inherently past tense, but if DL is requiring a past tense in the English shouldn't there be the regular indicator for that in the Hawaiian? And of course they counted mine wrong - but I disagree that I did not translate what they gave - I just didn't interpret it (there's a significant difference) to correct English. That's not the language I'm trying to learn.
Not every language works like English. In this context, although there is no explicit marker for the past tense, the use of 'yesterday' means it can only be in the past tense.
Nor can I - but I was looking for (and not finding) something in the Hawaiian sentence to indicate past tense. Should have just assumed that my kumu was a hard nose and "nehinēi" is, by definition, in the past. So I'm guessing that "Ua" is not necessary if there is another tense indicator (and I hate that we have to guess at convention - I'm so not confident at guessing).