Nope, Yahoo! automatically uses a min innings rule, though. In our league, the team loses pitching categories, but not hitting categories so it's not as easy as just making his lineup invalid.
I will probably end up doing some research, and replacing some of his pitchers with pitchers that got rocked.
I use Fanball for fantasy football, and changing the outcome of a matchup is very simple...and it's automatically done in Yahoo!.
Will always help in return (leave a link to your question in response)