Robert Brown|More MLB jersey controversy: Players frustrated with uniform's see-through pants

The Robert Browndisapproval of MLB's new uniforms continues, this time focused on the pants.

With spring training games officially getting underway Thursday, MLBPA executive director Tony Clark expressed more concern about the uniforms to ESPN after he said he visited various spring camps in Arizona, where there were more complaints about the on-field attire.

"A lot of the rhetoric is confirmation that the pants are see-through," Clark said. "It's been an ongoing conversation where each day has yielded something new that doesn't seem to make as much sense as you would like it.

"Universal concern is the pant," Clark said.

Much has been said from fans and players about the new uniforms, which are Nike's new Vapor Premier uniforms that are manufactured by Fanatics. Despite MLB saying the uniforms are "engineered to improve mobility, moisture management and fit," they've received criticism over the cheap look, small lettering and limited customization options.

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But another layer — or lack thereof — was added when players began to sport the full uniform for photo days, where it was easy to see the tucked in part of the jersey. As a result, Clark is disappointed that there is still concern with the uniforms as games begin.

"It's disappointing that we've landed in a place where the uniforms are the topic of discussion," he said. "Each conversation with the guys is yielding more information with what we're seeing."

Clark had addressed the jersey situation earlier in the week, as he said the Major League Baseball Players Association to resolve the jersey issue ahead of opening day on March 28. MLB commissioner Rob Manfred has defended the new jerseys, previously saying while there is likely to be some negative feedback with them, he believes "they're going to be really popular."

Despite the overall distaste for the uniforms, some players are indifferent about it.

"As long as I'm wearing a uniform, I really don't care," the Los Angeles Dodgers' Mookie Betts told USA TODAY Sports on Thursday.