ST. LOUIS -- After the Cubs' 5-3 loss to the St. Louis Cardinals on Saturday, Chicago manager Joe Maddon and pitcher Jon Lester ripped the slide rule, which cost their team a run in the close defeat.

"I have no idea why these rules are part of our game," a steamed Maddon said after the loss. "There was an out created there. That was just one out they did not have to earn. I totally, absolutely disagree with that. It has nothing to do with safety and protecting the middle infielder."

The play in question happened with one out in the top of the fifth inning and the Cubs trailing 3-1. Rookie Ian Happ, playing in his first major league game, slid into second base on Anthony Rizzo's ground ball back to pitcher Carlos Martinez. Kyle Schwarber, who was at third base, crossed the plate as Happ made a perfect slide but ended up a few feet past second base while shortstop Aledmys Diaz ate the ball after taking the throw from Martinez.

Diaz had no chance at a double play, but Rizzo was called out along with Happ.

A section of the rule, implemented in 2016, states that runner sliding into second has to make "a bona fide attempt" not just to slide into the base, but also to "remain on the base."

"When you're sliding on dirt and you have momentum, you just keep going," Maddon said. "There was no malicious intent there whatsoever. The rule does not belong in the game.

"There was nothing egregiously dangerous on the part of our runner. Don't give me hyperbole and office-created rules because I'm not into those things, as you guys well know."

Maddon also ripped into the slide rule at home plate, saying it doesn't belong in the game, either.

He wasn't the only one upset. Lester, who took the loss, also said he doesn't understand why the rule exists.

"Baseball has been played for over 100 years the exact same way, and now we're trying to change everything and make it soft," Lester said. "That's baseball, man. We're out there playing with a bunch of pansies right now. I'm over this damn slide rule and replaying if it's too far and all this other B.S. We're grown men out there."

Rookie Ian Happ, playing in his first major league game, was ruled out at second base due to the slide rule during Saturday's game. Chris Lee/Getty Images

Happ, who homered later in the game, didn't think he did anything wrong.

"Yeah, a little bit surprised, but they interpreted the rule the way it is by the book, and that's what happened," he said.

The play ended the inning and kept Schwarber's run from counting. The Cubs never got closer than the final margin.

Maddon ranted for over two minutes about the rule before moving on to other postgame topics.

"In general, we have a tendency to micromanage stuff that we have no business attempting to do," he said. "Don't give me all this protectionism, injury stuff because I'm not buying into it. ... It's wrong. It's tough for the umpires. They know it's not part of the game. ... I'd like to see that rule ejected. I'd like to see the rule at the plate ejected. They have no place in our game."

Lester just kept repeating he was "over the rule" -- as in, he was upset about it -- but he had to get it off his chest, as his manager did.

"The rule was meant to be for guys doing dirty slides," he said. "There's nothing wrong with that slide, whatsoever. ... There was nothing malicious about it, and we got two outs for some reason."