Boone said Tanaka was not exhibiting any symptoms and was in good spirits.
"He went through a battery of tests at the hospital; everything checked out well," Boone said Saturday, per Marly Rivera of ESPN. "He had a CT scan, and it's negative."
Tanaka also tweeted Saturday night that he was feeling OK:
Boone said Saturday that Stanton was a bit shaken up after the incident:
"A little bit of relief to see him walk off, and seemed to be at least OK immediately, and then we were able to let Stanton know a little bit later that he was doing well. I don't necessarily want to speak for G [Giancarlo], but he seemed to handle it as well as could've been expected. Any time you see that on a baseball field, and then add a layer that it's a teammate—that stops you in your tracks and you hope for the best. So that's one of those real unfortunate scary moments that happens every now and again in our game."
Tanaka, 31, finished the 2019 season 11-9 with a 4.45 ERA, 1.24 WHIP and 149 strikeouts in 182 innings (31 starts). He was one of the few prominent Yankees to avoid time on the injured list during the team's injury-riddled campaign.
Nonetheless, those Yankees went 103-59 and reached the ALCS, where they lost to the Houston Astros in six games.
Expectations remain sky high for the 2020 Yankees, even in a delayed and shortened season. Tanaka remains a vital part of the team's pitching staff, joining Gerrit Cole and James Paxton atop the rotation.