Much of this comes back to the same reasoning behind locking down players whose game is rained out. Our actual scoring is based upon official, overnight statistics. Completely independent of this, we get real-time stats during the days. However, this feed of data is subject to completely different constraints and guarantees, and is not official. If we get incorrect overnight statistics, we can correct them after the fact. However, if we get incorrect real-time data, and you change your roster based upon that, we can't put the toothpaste back in the tube and correct it; there is no room for, "I wouldn't have put that guy in my lineup if I'd realized that my other catcher actually played.", or whatever similar situation might arise. Now imagine the situation where one owner in a league gets caught by an inaccuracy in the unofficial real-time stats and another doesn't; that is an angry owner.  In situations like this, one of our guiding principles is to try to make sure that we can apply the same, consistent rules to all owners. If we ended up effectively basing the official scoring on your league on unofficial real-time data, we couldn't reliably guarantee that fairness. So even if the current state of things will sometime lead to arguably sub-optimal consequences, it is the same for all managers.  I agree with the consensus here that a roster spot should be locked in this situation.  However, I had another situation come up today with regards to locked roster spots that I'd be curious to hear thoughts on.  I checked my team around 0:00 to see if any of my players weren't starting in the 0 p.m. games, and saw that Ellsbury was not going to be in the lineup (game hadn't started yet). On my bench I had Melvin Mora, who was going to be playing (game hadn't started yet). Of course, Mora is not an OF... but in my IF spot I had the ever-versatile Chris Duncan, who had already played. I was hoping I could move Duncan from IF to OF (in no way gaining an advantage by knowledge of what happened in his game) and then slide Mora in at IF. Alas, no can do.  I'm not mad about this in the slightest, but it did get me thinking that it would be cool if we could move players who had already played to different positions in our lineups as long as we don't remove them. You really don't get any knowledge advantage here, it just gives you some added flexibility. Anyone agree? Disagree?  