HOUSTON -- Justin Verlander threw 17 sliders in Game 2 of the World Series last Wednesday night at Dodger Stadium. Only one of those pitches produced a swing-and-miss, leading the Astros ace to suspect something might be amiss.

Verlander isn't alone.

A new controversy gripped baseball Sunday when Sports Illustrated published a report in which players and coaches from both the Astros and Los Angeles Dodgers said they believe that the World Series balls are slicker than those used during the regular season. The texture of the balls has made it more difficult for pitchers to get the proper grip when throwing certain pitches, particularly the slider, the players and coaches contended.

"I think the main complaint is that the balls seem a little bit different in the postseason -- and even from the postseason to the World Series balls. They're a little slick," Verlander said Sunday before Game 5 at Minute Maid Park. "You just deal with it. But I don't think it's the case of one pitcher saying, 'Hey, something's different here.' I think as a whole everybody is saying, 'Whoa, something is a little off here.'"

The composition of the baseball has been a popular topic throughout the season, in large part because of the record number of home runs that were hit, with many players and coaches suggesting the ball was harder. But commissioner Rob Manfred has repeatedly said the balls, manufactured in Costa Rica, undergo routine checks and meet Major League Baseball's standards.

In the Sports Illustrated story, MLB senior vice president of baseball operations Peter Woodfork said the only difference in the ball from the regular season to now is a gold-ink stamping used during the World Series.

"I know Mr. Manfred says the balls haven't changed, but there's enough information out there to say that's not true," Verlander said Sunday. "On the one hand, you can have someone who manufactures the balls [say] they're not different, and on the other hand, you can say people who have held the ball in their hand their entire lives are saying something's different. You value one [opinion] over the other. You take your pick."

In particular, Dodgers starter Yu Darvish and Astros closer Ken Giles have struggled to command their sliders during the World Series.

Darvish didn't get a single swing-and-miss on 14 sliders in Game 3 and was knocked out after only 1 2/3 innings, the shortest start of his career. Giles has been removed as Astros closer after getting hit hard in the 10th inning of Game 2 and the ninth inning of Game 4. In the latter appearance, he abandoned his slider almost entirely.

"I had trouble with the ball throwing a slider," Darvish said in the SI story. "It was slicker."

It's possible that the difference could be the result of how the balls are being treated with pregame rubbing mud. But Verlander said with certainty that the same type of mud is used on every ball before every game.

"You get some that are a little darker, some a little lighter, more mud, less mud. That's pretty normal," Verlander said. "I think there's a broader issue that we're all missing."

Not every pitcher has noticed a difference.

Dodgers lefty Rich Hill, scheduled to face Verlander in Game 6 on Tuesday night in Los Angeles, described the balls as "extremely consistent in the World Series and also in the playoff games, as well." If there's a difference in the texture of the ball, Hill suggested it might have to do with the weather.

"If it's colder, it's going to be slicker," Hill said. "If it's a little bit warmer out or humid, I think you're going to find that you're going to have a little bit more moisture to the baseballs."

Likewise, Astros manager A.J. Hinch said he hasn't detected any changes to the baseball. Then again, Hinch said, he isn't a pitcher.

"I don't see a ton of difference," Hinch said, "but I'm not going to get in a verbal war with coaches and players who think otherwise. They're entitled to their opinion."