OAKLAND -- There are some hidden depths to the A's trade with the Cubs for Jeff Samardzija and Jason Hammel.
One of which is that it is a pre-emptive strike at the rest of Major League Baseball's contending teams, almost all of which believe they need more starting pitching.
The Yankees do. The Orioles do. The Blue Jays do. And the list is long.
With this one move, Oakland has taken three pitchers out of the mix. Three, because it's best not to forget that while he's limped along this year after being demoted by the A's, Dan Straily, who was sent to the Cubs, was a 10-game winner last year.
Straily, too, would have been a candidate to be traded somewhere in the run-up to the July 31 trade deadline.
The A's already had as deep a corps of starting pitching as any team in the game. Now it's deeper. And that's good.
Starting rotations elsewhere are shallower, and from the A's point of view, that's good, too.
Oakland's starting rotation numbers were excellent before this trade, but they only had two pitchers who figured to be ace-type material in the postseason, Sonny Gray and Scott Kazmir. Now they have three with the addition of Samardzija.
In the postseason, you need three. The A's learned that in the postseason the last two years watching the Tigers move past them in 2012 and 2013 thanks in part to having better starting pitching. Should the two teams meet again, the playing field as far as the starters vs. starters goes will be more level.
The A's are counting on that.