Why MLB warned Giants players who wrote Bible verses on Pride Night hats

Days after three Giants pitchers wrote Bible verses on the team's Pride Night hats, the league office is pushing back.

MLB responded to the controversy on Monday, issuing a warning to players not to write on caps after the decision by Giants players during Friday's game against the Cubs drew backlash.

The warning comes after first-year Giants manager defended his players' ability to "have the freedom to do what they think is best" when asked about the writings.

Here's a look at which players wrote Bible verses on the Giants' Pride Night hats and MLB's response.

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Which Giants players wrote Bible verses on Pride Night hats?

Pitchers Landen Roupp, JT Brubaker and Ryan Walker wrote Bible verses on the Giants' Pride Night caps on Friday. Reliever Sam Hentges, meanwhile, entered the game with a standard cap rather than the Pride Night design.

The verse on Roupp's hat, Gen 9:12-16, refers three times to rainbows as a sign of God's covenant with the Earth.

"Whenever the rainbow appears in the clouds, I will see it and remember the everlasting covenant between God and all living creatures of every kind on the earth," the Book of Genesis reads.

After the game, Roupp explained to reporters why he chose to write the verse on the hat, which featured the Giants' "SF" logo in rainbow colors.

"It's just about God's covenant and a promise that he makes to us that, you know, his faithfulness and his mercy," Roupp said. "That's just kind of something I believe in, and I stand firm in that, and I'm thankful we live in a country where, you know, we have the freedom to believe what we want."

Here's MLB's response to the decision by Roupp and his teammates.

MLB responds to Bible verses on Pride Night hats

An MLB spokesman told Outsports that wearing a cap with writing on it during a game is a violation of the league's rules regarding uniforms.

"The writing on the cap violates our rules and consistent with normal practice we have warned the players about future violations," MLB chief communications officer Pat Courtney said.

It's unclear whether the league warned the three Giants players in particular or sent a memo throughout the league, but MLB is pushing back on the action for what it considers to be a uniform violation. 

According to MLB rules, "no alterations, writing or illustrations, other than as authorized herein, are to be made to any part of the uniform."

Some players, including Dodgers reliever Blake Treinen, have opted to wear their team's regular cap rather than the Pride Night cap under similar circumstances this season; by all indications, MLB does not find that to be a rule violation.

Roupp, Brubaker and Walker have not been fined by the league. Outsports couldn't find any record of MLB fining a player over a uniform violation in the last decade, so a warning appears to be standard before any more action is taken.