Yankees outfielder Clint Frazier will likely be out for the remainder of the season after experiencing lingering post-concussion symptoms, manager Aaron Boone told reporters on Wednesday, per the New York Post.

On Aug. 30, Frazier joined the Tampa Tarpons to begin his rehab assignment but went to see a neurologist in Pittsburgh this week when his concussion symptoms started back up.

"As he was getting ready to get transferred to Double-A Trenton, he started feeling symptoms, so he went up there and saw this guy and trying to really hone in and get the best program in place we can for him to start getting him on the right track for good," said Boone, after Wednesday's 8-2 loss to the Oakland Athletics.

The 24-year-old was first hurt in a spring training game back in late February when he hit his head on the left-field wall trying to make a catch. Originally, he was said to have a "mild concussion," and a reasonably quick return was expected but he has been on and off the disabled list for the majority of the season.

He was playing at Baltimore with the Yankees in the middle of July when, while running between second and third base, he made contact with Orioles third baseman Jace Peterson. According to the team, the collision with Peterson brought about post-concussive migraines.

Frazier told reporters of the problems he was having post-concussion, like his sensitivity to light and that he forgot his cats' names.

The Yankees are expecting Frazier to make a full recovery.

"I'm hopeful, confident that he will," Boone said. "But then again, it's been a year of trying to get our hands around what's going on with him and trying to get him moving in the right direction with momentum and hopefully this is a step in that direction."

The re-occurrence of post-concussion symptoms limited Frazier to just 15 big league games this year. Frazier hit 265/.390/.353 with one RBI in 34 big league at-bats. He also played 48 games for Scranton/Wilkes-Barre and six for Tampa, hitting .305/.388/.562 in the Minors.

"We know there's a lot of talent that he possesses ... and we still believe he'll be a very important part of our franchise going forward."