MLB had already announced a bevy of rule changes coming to its minor leagues this season, but the biggest one may be heading to one of its partnered independent leagues.
The Pioneer League announced Tuesday it will be replacing extra innings with a home run derby to settle games tied at the end of nine innings. Under the new rule, teams will select a hitter who will receive five pitches at the plate. Whoever hits more homers wins the game, while a tie means a sudden-death round.
It's a system not unlike the shootouts seen in regular-season NHL games following a single overtime period.
Teams will also be allowed to use a "designated pinch hitter" and "designated pinch runner," which basically means being allowed to bring a player back into the game after a pinch hitter or runner was used for him.
The Pioneer League is an eight-team league operating in the Rocky Mountains that used to be affiliated with MLB and its clubs at the rookie ball level. Those teams lost their affiliation due to MLB's overhaul of the minor leagues last offseason.
Under the partner league designation, the Pioneer League collaborates with MLB in initiatives to provide organized baseball to help expand baseball's geographic reach, per MLB's site. That collaboration apparently includes rule experimentation.
MLB going big on minor-league rule changes in 2021
Replacing extra innings with a home run derby is probably the most drastic adjustment coming to the minor leagues now, but it still has competition thanks to MLB's decision to use its lower leagues as commissioner Rob Manfred's personal laboratory this year.
The Atlantic League, another MLB Partner League, announced its own slate of rule changes earlier this month. The big one is moving the pitcher's mound back a foot, which could theoretically cut down on strikeouts and help offense at a time in which balls in play are becoming increasingly less frequent at the MLB level. The league is also trying out a rule in which teams are only allowed a designated hitter when their starting pitcher is still in the game.
MLB's affiliated leagues aren't immune to the rule changes either. From Triple-A to Low-A, each league is adding a new rule this season, including robot umps, pitch clocks, larger bases, limits on pick-off attempts and restrictions on shifting fielders.
Could some of these rule changes come to MLB? Possibly. MLB has been aggressive in recent years with rule changes, most notably the extra-inning runner rule being used this season and the universal designated hitter seen last year and possibly next year.
Manfred has made no secret of his eagerness to change the game to make it more viewer-friendly, and any of these changes could be on the table if the league likes what it sees as they're implemented.
More from Yahoo Sports: