Rarely did they swing at pitches out of the strike zone. They knew which pitches to take, and only every once in a while did they look fooled by an opposing pitcher.
Robinson immediately knew what he wanted to preach during Spring Training. The best way to beat the league's elite is with an equalizer -- the changeup.
"The better it is, the more it looks like a fastball, and that's what they want to hit -- the fastball," Robinson said. "They go out to get it and it's not there yet. If we expect to compete and to beat teams like that, we need to have that pitch -- whether you're a starter or reliever."
For power pitchers like Roy Oswalt, the changeup can be a nice backup to complement his fastball-curveball arsenal. For finesse pitchers, it can often make them unhittable, a la Greg Maddux and Tom Glavine in their primes. For a reliever, it can be the driving force en route to the all-time saves record. Just ask Trevor Hoffman.
When Astros pitchers arrived to camp this year, Robinson was ready with his speech. In a nutshell, it went like this: The changeup is your friend. Practice it. Learn it. Use it.
The response, according to Robinson, has been favorable.
"I could not be more pleased with how guys have taken this to heart," Robinson said.
In layman's terms, the changeup is designed to confuse the hitter. Everything about it, from the delivery to the arm speed and arm slot, looks like a fastball. But it comes out of the hand about 10 mph slower than the fastball, and the hitter, expecting a higher velocity, is often too early with his swing.
The difference between a changeup and fastball is the grip. The index and middle fingers are used to throw a fastball, but to throw a changeup, the index finger typically fuses with the thumb to form a circle on the side of the ball, while the middle, ring and little fingers grip it.
"That's what kills the speed," Robinson said.
And keeps hitters off balance. Robinson's message impacted most Astros pitchers, including Chris Sampson, who remembers Nolan Ryan telling him that the circle changeup probably added at least five years onto his career.
Sampson, a former position player turned pitcher, has been working on the changeup for about four years, but only recently felt comfortable throwing it. In his first Grapefruit League outing last weekend against the Braves, Sampson estimated about half of his 41 pitches thrown were changeups.
"I need to work on mine," he said. "I finally found a grip that I'm comfortable with, and I just wanted to throw it and throw it and throw it to get better so I can use it in the season."
Sampson has extra motivation to develop his changeup, considering he's on the bubble of Houston's starting rotation. He was seemingly pushed out of the mix when Shawn Chacon popped into camp as a late signee, and while Sampson would prefer to start, he'll take any assignment. Looking to stay in the big leagues for as long as he can, and he sees the changeup as a good life preserver.
"My thing is I want to figure out a way to get better, so I can be here and stay here," he said. "If I can master the changeup, it'll be that much better. Might add some years. I just have to find a way to get better every year. Even if it's something minute. I have to find something."
Pitchers who have more job security have taken up the changeup as well. Astros starter Brandon Backe threw only fastballs and changeups in his first spring outing and held the Braves scoreless over two innings. Robinson mentioned veteran relievers Geoff Geary and Doug Brocail as quick studies and identified Brocail's changeup as "possibly one of the best on our staff."
Oswalt, who's been using the changeup for two or three years, sees advantages for a young pitcher to adopt a new pitch, but only if he doesn't lose the feel of his fastball. Concentrating too hard on the changeup, Oswalt argued, could have negative effects on a less experienced pitcher.
"If you don't locate your fastball, it won't matter if you have a good changeup or not," he said. "I think a lot of times in spring, kids get away from that. They try to master a breaking pitch or a changeup and they get away from spotting the fastball. If you don't spot your fastball, it doesn't matter what the other pitch is."
For most, the changeup is a work in progress. Robinson understands this better than anyone, and he makes sure to remind skipper Cecil Cooper during some of the less-than-spectacular outings this spring.
"I sit next to Coop [during games] and say, 'There's another changeup. That was a good pitch,'" Robinson said. "It's upsetting with the walks and the behind-in-the-counts, but I equate it to a lot of guys [being] in their first year in camp. A lot of guys are inexperienced, and the anxiety gets high for them. That's always going to be a factor. Hopefully, having one or two outings under their belt, they'll start throwing strikes."
Alyson Footer is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.