Perez went to the hospital to visit Chapman not long after the line drive off his bat struck the Reds' left-handed closer over the left eye in a frightening flash during the Royals' sixth inning at Surprise Stadium.
"He was doing pretty good. I saw him afterward, went to the hospital," Perez said on Thursday morning. "I talked to him and there were a lot of players there. He talked to everybody and knew who every person was. He was doing better."
Among the visitors were Royals pitcher Francisley Bueno and Reds catcher Brayan Pena, both of them, like Chapman, from Cuba. Chapman will remain at Banner Good Samaritan Medical Center for a few days.
Chapman suffered fractures above his left eye and nose and will undergo surgery to insert a plate and screws above the eye, the Reds announced. He had a mild concussion but his vision was not affected. It will be an estimated six to eight weeks before he can be back on the mound.
"I'm sad because he won't be ready for Opening Day," Perez said. "It's not my fault, I was just trying to do my job, he was trying to do his job. But I still feel bad about it."
Mike Moustakas was on deck when the ball struck Chapman.
"At first I thought he got a glove on it, and then I quickly realized that he didn't," Moustakas said. "Everything just stops and, at that point, nothing in the world matters except hoping that kid's OK."
Billy Butler was on second base at the time.
"It's just one of those things that rattles you. Everybody in the stadium is rattled," Butler said. "We all play the game because we love the game and because we're good at it and that kind of stuff just takes the fun out of it. You never want to see that happen to anybody. It makes you sick to your stomach."
"It's really disturbing, nobody wants to see that happen," said Danny Valencia, the runner at third base.
Chapman was treated at the mound for about 12 minutes, and when he was transported to an ambulance, the team managers and umpires decided to end the game at that moment.
Royals first baseman Eric Hosmer was the batter last June 15 at Tampa Bay when his line drive struck Rays pitcher Alex Cobb in the ear in a similar frightening incident. Hosmer used that experience to counsel Perez in the grim aftermath.
"It's a hopeless feeling because you realize you caused it and, obviously, you didn't mean to do it. It's a freak accident," Hosmer said. "Basically, I just told him, 'Go see him in the hospital wherever he is and it'll make you feel a lot better when you go to sleep tonight -- just knowing that he knows you care and you're out checking up on him.'"
Hosmer could relate to what Perez, who knelt at the mound while Chapman was being treated, was going through.
"I'm glad they ended the game like they did last night," Hosmer said, "because I remember when it happened in Tampa it was like the sixth or seventh inning and I couldn't even tell you what happened the rest of the game because my mind just wasn't in it."
Cobb missed two months before he returned to pitching for the Rays, and Hosmer followed his recovery with special interest.
"When he got back on the mound pitching, it really made me feel good. Especially when he had that playoff game against Cleveland last year, it was fun to watch," Hosmer said. "Guys like Alex and guys like Chapman -- those guys are competitors. You can't keep them off baseball that long."
The Royals' concern was clear as they gathered in the clubhouse on Thursday morning for a game against the Angels.
"It's something that you never want to see happen to anybody," Moustakas said. "Our thoughts and prayers went out to Chapman and his family, and we got some good news today that he's doing all right.
"But that's just something you never ever want to see in this game. Baseball is a big fraternity, and to see one of your brothers go down like that, it hurts. You feel for him and you feel for the entire Reds organization because that's one of their guys. It's just something real sad to see and it hurts for everybody."
Especially for Perez.
"For sure, I feel terrible," he said.
Dick Kaegel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.