OAKLAND -- For as electric as Ken Waldichuk looked in his Major League debut last week, the left-hander came away from that outing in Washington, D.C., with a clear idea of what he could improve on.

Command was the main area Waldichuk needed to address. Battling expected nerves in that first start, his four walks contributed to a high pitch count that ultimately led to an exit before he could complete five innings despite allowing only one run and striking out six batters.

Back on the mound Wednesday for his first start at the Coliseum -- just 15 miles south of Saint Mary’s College in nearby Moraga, Calif., where he starred as an amateur -- Waldichuk had much more control of his anxiety in the A’s 7-3 loss to the Braves, getting through 5 1/3 innings without issuing a walk as he limited the defending World Series champions to three runs on three hits with two strikeouts.

“His first start, I asked him what he felt out there, and he said, ‘I couldn’t feel anything,’” said A’s manager Mark Kotsay said. “Today, I think he did. He looked more relaxed. He got into the action right away and into the strike zone immediately. That definitely was an improvement from day one.”

During his first time through Atlanta’s potent lineup, Waldichuk retired eight of nine batters faced. His only blemish was an infield single by Travis d’Arnaud in the second as he efficiently navigated his first three innings scoreless on 49 pitches. 

The totality of damage allowed by Waldichuk really came down to two pitches that left the yard. After hitting d’Arnaud with a pitch to lead off the fifth, Vaughn Grissom pounced on a first-pitch fastball from Waldichuk and drove it over the wall in right for a game-tying two-run homer. In the sixth, Dansby Swanson’s solo shot on a 3-2 fastball marked the end of Waldichuk’s outing.

“Outside of the two home runs, he really pitched well today,” Kotsay said of Waldichuk. “He got us into the sixth inning. The Swanson at-bat, he makes a pretty good pitch 2-2 that could have got him, and then Swanson takes a good swing on a fastball up that he’d beaten him with earlier in the game.”

Of the two homers, it was the location of the one surrendered to Grissom that left Waldichuk more frustrated.

“The first one was just bad execution,” Waldichuk said. “It was supposed to be in and I left it out over the plate. Second one, I thought it was a good pitch and they hit it. One decent [pitch] and one bad.”

For the most part, Waldichuk’s fastball was still his sharpest pitch, and he relied on it heavily. Maxing out at 96.7 mph, he threw it for 59 of his 92 pitches, generating 40 swings and five whiffs (swing and misses) with the heater.

“His fastball can beat people, so he definitely has confidence in it,” Kotsay said. “He realized after his first start that these big league hitters can hit a fastball. It doesn’t matter how hard it is. I think today was a sign that he located it better. He threw it where he wanted to and more effectively.”

Command of the fastball helped make up for what Waldichuk said was a lack of feel for his offspeed pitches, particularly his changeup, which he only threw 13 times Wednesday as opposed to 20 times in his previous outing as one of his more effective offerings.

“That [fastball command] helped to be able to rely on that when I wasn’t really executing my offspeed too well,” Waldichuk said. “I think that was a pretty big difference-maker this time around.”

Ranked as Oakland’s top pitching prospect and the No. 70 overall prospect in the Majors per MLB Pipeline, Waldichuk’s arrival to the Major Leagues certainly came with a lot of hype. Given his demeanor on the mound Wednesday against one of baseball’s better offenses, the A’s believe he’s well-equipped to handle the extra buzz.

That’s why Kotsay had no hesitation throwing out the name of a Cy Young Award winner when the question of a comp for the tall left-handed rookie came up.

“I was asked earlier in the day who I’d compare him to, and Robbie Ray comes to mind a little bit,” Kotsay said. “That’s a lofty name to throw out, but I think there’s some similarities there.”