Well of those two I would have to pick Willis/Johnson, not only because it really was the best duel of the year, but because Harden/Pedro never happened. The only game Pedro started against Oakland, Hudson threw that 2hit shutout. Now, if you meant Hudson Vs. Pedro i still say no cuz that really wasnt a duel at all, that was just Hudson tooling on the sox and pedro gave up 2 runs over a measly 5 innings.
My vote goes to Millwood/Foppert. Funny thing is, we don't remember it as Millwood vs. Foppert because Millwood threw his no-no that day. The only thing about that game is that Foppert only went 6 innings...if he threw one more inning I thin it would be a lock for that game. Even still, I think that game was the best duel of the season.
True both games were dominated by one pitcher, but Foppert was considerably better against millwood than Pedro was against Hudson.
Rest in peace Mitch Hedberg. I name my fantasy team "Buoyancy of Citrus", in your honor.