Senzatela, 22, unexpectedly made the season-opening rotation and had a 2.86 ERA through his first seven starts. But inexperience and the demands of the Major League season led to some rough times, and convinced the Rockies to reduce his workload.
Since late June, seven of his 10 appearance have been in relief. He has used the time to regain the life on his fastball -- a pitch that, when he's effective, he can place to all four quadrants of the strike zone. Between appearances, Senzatela has improved his secondary pitches so he's not reliant on the fastball.
"I feel that if I go back to starting, I'll have three other pitches -- not just the fastball," Senzatela said after striking out two in two spotless innings to end Thursday's 10-4 loss to the Braves. "I'm going to try four pitches. But, really, I'm just going to try to get people out."
In the 10 games with a lighter workload, Senzatela has a 3.86 ERA with 26 strikeouts and 12 walks. According to Statcast™, he's using the fastball slightly less, 72.8 percent as opposed to 75 percent in his first 15 games, all starts. The velocity of the fastball is up slightly from 94.1 percent in his first 15 games to 94.8 percent since then.
Senzatela is also serious about mixing his pitches. During the last 10 games, the Rockies have Senzatela having worked in the slider 19 percent of the time, the curveball 6 percent and the changeup 2 percent. He stayed off the curve Thursday, but had an effective changeup.
In five games this month, including a five-inning start at Cleveland, he has a 2.57 ERA, 14 strikeouts and four walks in 14 innings. A couple of keys to the five-game success has been positive counts -- he has been behind just 34.1 percent of the time, and hitters swing and miss at 21.7 percent of breaking pitches (up from 13.7 percent before).
For a pitcher whose highest experience level before this year was 34 2/3 innings at Double-A Hartford last season, Senzatela has crammed in a lot of learning. Now comes time to put it to use for a club battling for the playoffs.
"I've been impressed with so much that 'Senza' has done," Rockies pitching coach Steve Foster said. "Controlling the strike zone, controlling the count, he controls the running game, he controls the tempo of the game.
"He has all these controls. When you can control your emotions as a young person, you're able to utilize the things that you've been taught."