DENVER -- Rockies right-hander Antonio Senzatela has steadily become more diverse with his pitching plans and, especially since the start of last season, more effective in his execution. One small problem: He was pitching Wednesday against the D-backs, who had hung a 6.19 ERA on him in nine career starts coming into the game.

Now the D-backs have experienced Senzatela’s growth firsthand.

Senzatela forced 14 groundouts, one of them a double play, holding his nemesis scoreless on four hits for eight shutout innings of the Rockies’ 8-0 victory at Coors Field.

During his pregame bullpen session, Senzatela’s slider was so electric, catcher Elias Díaz felt the pitcher’s night was destined to be special.

“When I walked out of the bullpen, Díaz said, ‘Your slider is good tonight -- use it,’” Senzatela said.

Senzatela finished the night chest-bumping and high-fiving Díaz after the catcher blocked a slider in the dirt and fired to third base to nab Tim Locastro on a tag play to end the eighth, an electric finish to Senzatela’s night on the mound.

Once a fastball-dominant pitcher, Senzatela spent much of his early career being prodded to use his secondary pitches. Progress was intermittent until his breakout 2020 campaign, when he was especially potent at Coors Field -- 3-0 with a 2.10 ERA in five starts, including the Rockies’ only complete game of the season, a six-hit, 3-1 victory over the Athletics on Sept. 15.

On Wednesday, Senzatela threw 96 pitches, 62 of them strikes. But how he mixed them raised eyebrows -- a career-high 43 sliders against 42 four-seam fastballs, according to Statcast. In his 2021 debut, his pitches stayed up in the strike zone and the Dodgers feasted on them, to the tune of nine hits and seven runs in 3 1/3 innings of an 11-6 loss.

There was risk in the slider-based strategy. He has done it on a handful of occasions, often with good results. But when he threw 36 sliders on June 22, 2017, against the D-backs, he gave up nine runs.

Clearly, he had a better handle of things Wednesday.

“I don’t want to give away any trade secrets, but he had a good slider tonight, for sure,” Rockies manager Bud Black said. “He and Elias did a good job of mixing pitches. The fastball was located better than his previous start.”

Senzatela also has returned to a changeup that was a weapon in the Minors, and that pitch was used sparingly but effectively Wednesday. After leading a decent Rockies rotation (despite a poor overall team record) with a 151 ERA-plus (100 is MLB average) last season, Senzatela now has another strategic option.

“Every year we learn something,” Senzatela said. “Back two years ago, I had a tough year. I’ve learned now how good my slider can be throwing it the way I am. I have more confidence in it.”