It all came down to Rios's apparent lack of hustle during the fifth inning -- a willful mistake that prompted Ventura to lift Rios from the game and replace him with Casper Wells in right. Here's how MLB.com's Scott Merkin described the play in question:
With runners on first and third and the game tied at 2 in the fifth, Rios hit a hard grounder to [Andrelton] Simmons that looked as if it would be an easy inning-ender.
Simmons bobbled the ball twice, but with Rios getting a slow start out of the batter's box, the double play was still turned without much of an issue. Rios was replaced by Casper Wells in right field in the top of the seventh.
After the game, Ventura confirmed that that Rios was lifted from the game for not running out that ground ball. "We expect more than that," Ventura said (source: CSN Chicago). "It was simple. Nothing more than that. ... I just told him he was coming out. That was it. He knows. There's not a long explanation required."
The timing is, to say the least, interesting. As CBSSports.com's Jon Heyman recently reported, the Pirates are among the teams interested in trading for Rios leading up to the July 31 non-waiver trade deadline. This in tandem with Rios's recent struggles likely isn't helping his value on the market.