New York announced that X-rays were negative, and he is listed as day-to-day with a contusion. He will get a CT scan Thursday.
"That's super promising that the X-rays are negative," Alonso said. "I mean we're going to get additional imaging with a little bone scan tomorrow just to double check. It's super encouraging but at the same time we want to see how the swelling plays, you know? Hopefully it goes down sooner rather than later, and I can get right back on the horse."
Alonso, who leads the major leagues with 22 homers, dropped to the ground after being hit by the 96 mph fastball. He got up and walked about halfway to first base before manager Buck Showalter and a trainer came out to tend to him. After a short meeting, Alonso walked off the field.
Alonso, who is batting .231 with 49 RBIs, was booed in pregame introductions and before his at-bat after shouting at Braves starter Bryce Elder, "Throw it again, throw it again, please! Throw it again," a night earlier following his long homer in a 6-4 loss to the Braves.
Some fans cheered when Alonso was hit by the pitch, but the New York first baseman said he harbors no ill will.
"Yeah, I think obviously that's a consequence of what I said in the dugout and the hot mic," Alonso said. "It's just unfortunate because I think it got blown out of proportion. It's just friendly competitive banter. I guarantee you if you were to mic both dugouts, you're going to hear certain things that people could take offense to, but for me I didn't mean anything by it."
The Associated Press contributed to this report.