So far this year, the O's have gotten 28 starts from pitchers other than Hammel, Chen, Tillman and Gonzalez. 16 of those could be seen as "fifth starter" starts, with the rest replacing starts missed by Chen and Gonzalez. In those 28 starts, the starters have averaged 4.99 innings per start, and posted an ERA of 6.64. They posted a 6-13 record, and the team went 12-16 in those starts.
Enter Scott Feldman. I am not expecting him to match his 2013 ERA for the Cubs pitching in our division. But if he can give us 16 starts with an ERA around 4.50 and average 6 innings per start, and post a .500 record, we're way ahead of the game.
That's maybe 16 fewer innings the bullpen needs to throw, and maybe 19 fewer runs the team will allow, compared to before the trade.
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