Each of his last two outings has been far and away better than his first, during which he hit three batters and walked another in a disastrous display against the Angels. On Saturday he didn't issue a single free pass.
"After his first outing, I knew that wasn't him," said second baseman Joey Wendle, who also played behind Alcantara at Triple-A. "I knew he had a lot more in the tank than that, and he proved that tonight. It was really cool to see. That's a strong lineup over there, but he's a good pitcher."
Alcantara, 23, was beaming when asked about earning his first Major League win, acknowledging through interpreter Alex Arpiza, "This is very important for me.
"I'm achieving my goals. I really wanted it from my first start," he said. "Just to go out there and not think about them being a potent lineup, just to locate my pitches, I feel like I'm growing confidence."
"You could see his confidence grow as the game went along, especially after the first inning," manager Bob Melvin said. "For a guy that got off to a little bit of a rough start with his first outing, he's really recovered well, and when he's throwing the ball over the plate, his stuff is going to play, and he's going to have success."
Alcantara, who began the season at Double-A, worked around a two-out single to strike out the side in the first inning, and he notched one more strikeout by the time he departed, having tossed 85 pitches.
"Ran out of gas a little in the sixth, but he was getting some funky swings from some really good hitters, so it was good to see," Melvin said. "I know he feels good about the outing, and it gives you a lot of confidence going forward knowing you can pitch against a lineup like this and have some success."
Said shortstop Marcus Semien: "He seemed very relaxed. Big stage, big crowd here, Saturday night, and he stayed very calm. From his first outing until now, it's been a drastic change."