I'm not gonna say there's a perfect right and wrong answer to this, but I think it's a tricky line to walk. We know the back end of the pen is a bit thin with Alzolay's injury, Merryweather being down, and Fulmer not having pitched in a game in 2 weeks. Warming guys up comes at a cost, and I understand trying to minimize that cost where you can. In the case of Cuas' outing, he didn't get to a 2 ball count until the 4th hitter, having gone K, K, groundball 1B. The 4th hitter was HBP on a full count(dubiously, I still contend), and only then did things go particularly poorly. Even then he was facing bad, same-sided hitters at the bottom of a bad lineup, so the matchup wasn't especially poor. In order for him to have gotten pulled any earlier, you would've had to start warming a reliever after the 2 out single, which while not indefensible I don't think is unreasonable under the circumstances to let ride a bit further.