But young arms are precious and fragile commodities, and A's manager Bob Melvin has noted in recent days that the team will be watching the innings of pitchers like Doolittle and Cook, as well as the trio of rookies in the starting rotation. Doolittle's is an especially unique situation, since he didn't begin pitching professionally until last year.
Melvin's comments were spurred by the fact that this week marked the first time Doolittle pitched in back-to-back games, and Cook in three straight. It could potentially be a problematic area -- the pair has pitched very well, and any manager wants his best hurlers to be available as much as possible.
Still, Melvin said it isn't difficult to decide to hold out his young pitchers because the team is well aware of how important their future is, too. And Doolittle and Cook agreed, saying before Saturday's and Sunday's games, respectively, that they trust Melvin to make the best call.
"At the same time, there have been times where it's frustrating, where I feel good enough to go, and because they're being careful," Doolittle said. "But at the end of the day, I understand that on some level their hands are tied.
"We'll see how it plays out, but I understand the uniqueness of the situation."
Another dynamic, at least for Cook, is how his performance has suffered when used a lot. He hasn't allowed a run in 33 innings pitched with at least one day's rest, while he's given up eight runs in 7 1/3 innings with no rest.
Cook insisted he hasn't felt any different physically when pitching without rest, and pointed to it just being a small sample size.