But unusual doesn’t mean incorrect. While I’m sure there will be plenty of people arguing that the Blue Jays should have taken the path of least resistance and upgraded the pitching staff instead, the reality in baseball is that a run is a run is a run. You win games by outscoring your opponents, and you don’t get any less credit for winning 7-5 than you do 5-3. Troy Tulowitzki will help the Blue Jays score more runs, so while he’s not going to help the team’s run prevention improve that much, those runs he creates will still count in the final tally.
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How big is that upgrade? Over the remainder of this season, the gap between the two shortstops is estimated at roughly one win, or roughly the same upgrade the Astros got by adding Scott Kazmir to their rotation, and again, that’s without considering the non-linear nature of run scoring. So, while going from Reyes to Tulowitzki might not be quite as impactful in 2015 value as landing a guy like Johnny Cueto, the upgrade is along the same lines as adding any of the next tier of pitchers.
for all the advanced stats that get thrown around here, it seems silly to avoid the obvious.