The "Chase Utley Rule" is already causing steam to rise from the ears of MLB managers.
The Tampa Bay Rays won a game-ending replay challenge Tuesday night, successfully arguing that Toronto Blue Jays outfielder Jose Bautista violated a new edict that essentially prohibits a baserunner from going out of his way to interfere with a fielder who is trying to turn a double play.
Toronto manager John Gibbons was livid afterward. "Are we trying to turn the game into a joke?" he said. Some fans are also upset at what they perceive is a softening of a storied sport.
With bickering over the new regulation already in full effect, we look back on some of the most notable and controversial sports rules changes in recent decades.
Chase Utley Rule, 2016: After Utley broke the leg of Mets infielder Ruben Tejada in the 2015 postseason with a vicious, late slide that started wide of the bag and ended with Utley several feet past second base, MLB decided to clean up the rules on slides. Rule 6.01 (j) reads that the runner has to make a "bona fide slide" and should be "able and attempt to remain on the base (except home plate) after the completion of the slide." To be clear: There had always been rules governing breaking up double plays; umpires had simply rarely enforced them. The new rule attempts to codify more specifically what constitutes interference.
Neighborhood play, 2016: Also new -- in conjunction with the slide rule -- is that MLB has officially killed instances where an infielder turning a double play doesn't have to actually touch second base to get the out. The neighborhood play, a product of history as opposed to the rule book, will now be subject to video review. It existed to protect middle infielders who were exposed on double plays, but with the Utley Rule in effect, the thinking goes, that's no longer a concern.
Buster Posey Rule, 2014: Posey suffered a season-ending ankle injury in 2011 when Marlins outfielder Scott Cousins veered off the baseline to ram the Giants catcher, sparking a reinterpretation of Rule 7.08 (b) that was enacted to eliminate egregious home plate collisions. The highlights of new rule 7.13: A runner may not run out of direct line to the plate in order to initiate contact with the fielder; the catcher may no longer block the path of the runner unless he has possession of the ball; runners are not required to slide. Essentially: The catcher must provide a runner a lane to the plate unless he has the ball, and the runner can't go out of his way to crush the catcher.
Auto-ejection for two unsportsmanlike conduct penalties, 2016: Commissioner Roger Goodell spearheaded this yellow card-like rule, designed to curb overaggressive behavior outside the normal parameters of the game. Its impact is unclear -- only two players would have been ejected in 2015 had the rule been in place then -- but coaches are worried about opponents baiting key players into unsportsmanlike acts to capitalize.
Banning touchdown celebrations, 2009: Putting the "No" in "No Fun League," the NFL banned all celebrations other than simple spikes, dances and Lambeau Leaps. The rule has continued to be adjusted to address player creativity and now outlaws props, going to the ground or collaboration with teammates.
Limiting hits to "defenseless receivers," 2009: This rule makes sense from a health and safety standpoint but has proved to be vexing for players, fans and officials. It prohibits contact by a defender's head, forearm or shoulder to the head or neck area of a defenseless receiver. In many cases, seeing the actual point of contact is extremely difficult.
Eliminating hand checks, 1994: NBA basketball in the mid-1990s was a full-contact sport. Defense resembled hand-to-hand combat, especially during the playoffs. Players struggled to score as defenders clutched, grabbed and arm-barred opponents and the game into submission. The league eventually decided it wanted a more pleasing offensive game and began outlawing physically restricting forms of defense, starting with the hand check. The use of forearms by defenders was subsequently eliminated.
Zone defense legalized, 2001: Heading into the 2001-02 season, the NBA disassembled many of its complex illegal-defense rules. Notably, variations of the zone became legal, allowing defenses more leeway in double-teaming dominant players such as Shaquille O'Neal. The defensive three-second rule, which prohibited defenders from clogging the lane instead of guarding an opponent, was also enacted. Further, the amount of time offenses had to advance the ball past half court was reduced from 10 seconds to eight. All of the above changes have allowed offenses to become more free-flowing, and scoring continues to increase.
Back-pass rule, 1992: Following criticism at the 1990 World Cup, FIFA moved to eliminate the delaying tactic of a defender passing the ball back to his goalkeeper. Beginning at the 1992 Olympics in Barcelona, with a match between Italy and the United States, goalkeepers were no longer allowed to use their hands to field the ball on such plays.
Tackling from behind, 1998: In a move to reduce injuries, the International Football Association Board made aggressive sliding tackles from behind punishable by red card. The rule was implemented at the World Cup that year.
Shootout, 2005: Coming out of the lost 2004-05 lockout season, the NHL wanted to improve the quality of offensive play. It adopted a shootout to determine a winner in games that remained tied after regulation and a five-minute, four-on-four overtime period. Postseason games were unaffected, with the winner still determined in sudden-death overtime -- no matter how long it takes. Some observers panned the move as a gimmick, but it eventually became an accepted part of the game.
Two-line passes legalized, 2005: Another move to increase scoring coming out of the lockout was the elimination of offside at the center line. With two-line passes legal, longer scoring chances became possible. But critics have opined in recent years that some players' tendency to wait for the puck by posting up at the blue line has made the game too predictable.
Three-on-three overtime, 2015: In an effort to create more open-ice scoring chances in overtime and reduce the number of shootouts, the league reduced the number of skaters from four to three per team. Entering this season's All-Star break, 64 percent of overtime games were decided in extra time -- up 20 percent from 2014-15.
Chris Ramsay, David Schoenfield and Kevin Seifert of ESPN.com contributed to this report.