The Kansas City Royals placed left-hander Ryan Yarbrough on the 15-day injured list Monday with what was classified as "head fractures" after he took a 106 mph line drive off the right side of his face Sunday.
Royals manager Matt Quatraro said Yarbrough has three non-displaced fractures in different spots around his right eye.
"He's stable, improving," Quatraro said before Monday's game. "He never lost consciousness. He's very aware of what's going on around him. We don't think at this time [the injuries] will require surgery. He's getting further testing, and we'll have a better idea [of his prognosis] in the next 24 hours."
Quatraro was one of several Royals who stopped by the hospital after Sunday's game against the Oakland Athletics.
"If you weren't looking at him, the conversations were totally normal," Quatraro said. "You wouldn't know anything was going on."
Yarbrough, 31, was hit just above his left temple by a line drive from Oakland first baseman Ryan Noda in the top of the sixth inning. Yarbrough immediately crumpled to the ground, while the ball ricocheted back toward home plate.
Royals catcher Salvador Perez fielded the ball and threw it to first base for the out.
Yarbrough was tended to by Royals medical personnel and walked off the field with some assistance while holding a towel to his face.
Quatraro said Noda reached out to Yarbrough via social media.
"Out on the mound at the time, what he said was, 'I think I'm done. My head is ringing,'" Quatraro said. "That makes perfect sense.
"We're going to have a lot better idea in the next day or so. If you think about broken bones that don't require surgery, they heal within four to six weeks. But that's just for those bones. He has to have activity and those types of things."
Right-hander Jose Cuas was recalled from Triple-A Omaha. He relieved Zack Greinke with two out in the sixth inning Monday and retired the only batter he faced, then watched as Kansas City's offense handed him the win in the 12-5 victory.
Yarbrough is 1-4 with a 6.15 ERA in 10 appearances (three starts) with the Royals this season. He spent his first five major league seasons with the Tampa Bay Rays and is 41-35 in 137 appearances (62 starts) with a 4.41 ERA.
Cuas, 28, was 1-0 with a 5.65 ERA in 14 appearances earlier this season with the Royals and is 6-2 with a 4.15 ERA in 62 relief appearances with Kansas City over the past two seasons.
Reuters and The Associated Press contributed to this report.