Manager Aaron Boone was not hyperbolizing by saying the New York Yankees "dodged a bullet" with pitcher Masahiro Tanaka seemingly being symptom-free just a day after being hit on the right side of the head by a 112 mph line drive from Giancarlo Stanton.

After he underwent a battery of tests, Tanaka's official diagnosis was simply a "mild concussion," and he was released from NewYork-Presbyterian Hospital on Saturday night. Astonishingly, the 31-year-old right-hander was back at Yankee Stadium on Sunday.

"He came in around noon today and was in really good spirits," Boone said. "Got a really good night sleep; no loss of appetite. We're encouraged where he is and we'll take it day by day, but hopefully it's not something that'll take too long. Since he got to the hospital, he's pretty much been symptom-free and feeling good ... [was] in good spirits popping around today, so I think at this point we're really encouraged."

"First and foremost, a very scary incident, something that when you do what we're doing, it's tough to avoid," said outfielder Brett Gardner. "We've seen him here today, walking around acting like his normal self, so I'm hoping that he's in the clear."

Left-hander James Paxton, who threw live batting practice on the second official day of workouts at Yankee Stadium, made a point of using an "L screen" as a safety mechanism. Fellow left-hander Jordan Montgomery, who followed Tanaka with his own sim game on Saturday, had also requested the protective screen, which is generally used for BP sessions but rarely for simulated games.

Paxton, who was 15-6 with a 3.82 ERA for the Yankees in 2019, said he has returned to full health after undergoing a microscopic lumbar discectomy in February to repair a herniated disk and remove a peridiscal cyst.

"What happened yesterday was so scary. After seeing that happen, I just wanted to play it safe, especially first time out there," Paxton said. "Luckily it doesn't happen very often, but I just wanted to play it safe the first time out. Next time it'll be more of a sim game setting, so the screen won't be out there. But, especially after yesterday, it was a conscious decision just to have it out there for safety."

He added: "When a ball comes back at you that hard, there's really not much you can do. You kind of just get lucky if you put your glove in the right spot. That ball came back, I think they said 112 mph, and there's really nothing you can do about that. You just pray that it doesn't happen."

Boone also said that besides DJ LeMahieu and Luis Cessa, who are isolating at home after testing positive for COVID-19, the rest of the team was healthy through the first two days of full-squad workouts at Yankee Stadium.

Catcher Gary Sanchez and closer Aroldis Chapman, who were not at the stadium the day before because they had not finished intake protocols, took part in Sunday's workout. Chapman threw a bullpen session and Sánchez was one of the three hitters to face Paxton during batting practice, along with Miguel Andujar and Tyler Wade.

The Yankees will hold two evening intrasquad games this week, with J.A. Happ starting on Monday and Gerrit Cole scheduled for Tuesday night's game.