You've listed 4 pitchers out of probably about 40 guys that pitched in the WBC. I have no clue how they're doing, they may all be terrible too. But 4 pitchers' stat lines is proving nothing. Clarifying, 40 was an estime on the # of MLB pitchers from the WBC, not the total. There were far more than 40 pitchers in the WBC. Throwing 140 pitches is repeating a stressful activity over and over again. There is a small sample of 140+ outings to go off of, but from what I've seen the negatives that come from it are far greater than 10%. I don't think there's any evidence right now other than some circumstantial evidence that some guys who happened to pitch in the WBC had rough starts. You mentioned significant innings earlier. Brad Lidge pitched 2 innings. Johan Santana pitched 8.1 Zambrano threw 6.2 Garcia threw 7.1 Is this really considered significant? And I think calling it high risk is pretty out there based solely on the slow starts of some good pitchers. Good pitchers have slow starts every year. There's not always a reason for it, other than just having a slow start. I never said it's not possible that the WBC is bad for pitchers, but I don't think a month's worth of stats is the compelling evidence to convince me. I don't understand the timing complaint as pitchers were pretty much on schedule with where they would be in spring training. There's an emotional tug if you're in a pennant race too, but I don't think there's been any evidence that pitchers who are in tight races perform poorly in the postseason. I don't see how emotions being involved is going to wind up making you a poor pitcher the first month of a season. The only effect I can think of involving emotions would be a pitcher overthrowing in the WBC games, which would just lead to poor WBC #s, not MLB #s.