The New York Yankees placed first baseman Anthony Rizzo on the 10-day injured list with post-concussion syndrome, manager Aaron Boone announced to the media on Thursday.
Boone said the club believes Rizzo's symptoms trace back all the way to May 28, when the 33-year-old was involved in a collision with San Diego Padres star Fernando Tatis Jr. at first base while fielding a pickoff throw.
Rizzo exited the game following the collision and missed the next three contests due to a stiff neck. Boone said Rizzo passed MLB's concussion protocol before returning to the field on June 2.
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But Rizzo recently mentioned feeling "foggy" to the club's medical staff, according to Boone. After being run through neurological testing, the results showed Rizzo was “moving a lot slower than the normal person’s reaction time would be," the first baseman said.
"That's definitely alarming, especially for what I do for a living," Rizzo added.
Rizzo, who's considered week to week, hasn't been the same player since returning from the collision. He opened the season hitting .304/.376/.505 with 11 home runs and 32 RBIs through May 28. But he's slashing just .172/.271/.225 with one homer and nine RBIs since.
The three-time All-Star called the diagnosis a "silver lining" as he's struggled to find his way out of a prolonged slump.
"I've struggled plenty in this game, but I've also done it for a long time to know that you usually come out [of a slump] and there's signs of coming out," Rizzo said. "I remember talking to someone [who asked], 'Do you feel like you're coming out of this soon?' I answered honestly and I'm like, 'No, I don't.' Because I just couldn't feel what you're trying to feel as a hitter. I guess now we can link two and two together.
"[The diagnosis] came back with a silver lining that I'm not crazy for walking back to the dugout consistently thinking, 'Man, how did I miss that pitch? I usually don't miss that.' Or when I swung at a pitch thinking it was in one location and then going and looking at the video and it's in a different location. As a baseball player, that's frustrating."
