Everyone knows Eli Manning is the New York Giants’ star attraction at quarterback.

How many know that Ed Skiba, a 5-foot-5, 140-pound assistant equipment manager who has never played quarterback at any level, is the Giants’ second most famous passer?

Videos of Skiba throwing footballs have accumulated millions of views on the Internet. Similar snippets of his passing have become a Twitter phenomenon. Before Giants games, fans in the stands cram the rows next to where Skiba is tossing a football. No one wants to miss the result of a single flick of his wrist.

“It’s really pretty funny because my passing mechanics are horrible,” Skiba said last week.

But throwing the football poorly is what has led to Skiba’s popularity. That is because Odell Beckham Jr. — the Giants wide receiver famed for what may be the best one-handed pass reception in football history — likes to practice making nearly impossible catches of wayward passes before every Giants game.

Beckham has chosen Skiba, a 41-year-old from New Jersey who has worked for the Giants for 20 years, as his designated bad passer.

Skiba has become a featured player in a can’t-miss pregame show akin to performance art, or Cirque du Soleil.

With Skiba flinging the ball errantly on purpose, Beckham catches footballs thrown 5 feet over his head, 10 yards in front of him, inches behind his head or millimeters from the ground. He lies on his back, facing away from Skiba, and snags passes thrown just in front of his face as he does bicycle kicks. Some passes wobble haphazardly or tumble end over end. That is how Beckham wants it.

“Skiba does a good job,” Beckham said. “He knows how to throw the ball in all the wrong places. Well, the right places.”

Manning has scrutinized Skiba’s act.

“There is an art to it,” said Manning, who has been named the most valuable player in two Super Bowls. “Growing up, we always played a game called amazing catches. My dad would throw it where we would have to lay out for the catch. My dad was pretty good at it.”

Standing in the Giants’ locker room where Skiba is a common, hustling presence — a diminutive man scooting in between behemoths — Manning added with laugh, “I don’t know if Skiba’s that talented or knows where the ball is going.”

Skiba began working with Beckham during the Giants warmup period almost by accident before a game last fall. Victor Cruz, then the Giants’ top receiver, had another staffer tossing him footballs at the end of various pass routes. Beckham turned to Skiba, who, like most of the equipment staff, always seems to be around the players, and asked, “What are you doing right now?” Skiba replied, “Nothing.”

Beckham flipped Skiba a football and told him what kind of pass he wanted. And he kept changing the assignment.

“Odell is a perfectionist,” Skiba said. “He works very hard at making those impossible catches look easy. And it’s not just one-handed catches. He’ll have me throw passes where he has to reach over and behind his body to get the ball. What he’s doing is trying to simulate a game situation where he has to reach over and behind a defensive back to make a catch.

“He wants to replicate really hard game conditions where the ball is not where any receiver would want the ball to be.”

Now a year into their collaboration, Skiba and Beckham communicate on the field mostly through hand signals. Beckham wears headphones before games but gestures to Skiba with a point of his finger, a wave of his hand or by motioning his arms.

Skiba tries to make the pass Beckham has requested, and if he fails, that might be good.

“Those become another tough pass for Odell to practice with,” said Skiba, who grew up about 10 miles from where the Giants play and practice. “And Odell will probably catch it anyway.”

Beckham said his pregame routine is not usually scripted.

“There might be one thing I’m working on, but after that, I go by how I feel,” he said. “We kind of roll with it.”

Skiba said he could hear the cheering crowds that now gather to watch Beckham’s 20-minute warmup. He never mistakes the ovations as being for him. “But I have noticed that the pregame crowds watching are getting bigger and bigger,” Skiba said.

It has not led to newfound fame for Skiba.

“The only thing that’s happened is that the guys on my softball team bust me even more now,” Skiba said. “They say I can’t throw.”

Nonetheless, Skiba is renowned in pro football circles. He’s the other guy — the one not named Eli — throwing to Beckham. And his passes will be preserved on YouTube forever.

About a year ago, Skiba had his first child, who goes by E.J., short for Edward Joseph. Last week, Skiba was told that when his son grows up, he will be able to go on the Internet and see videos of his father’s handiwork.

“He’ll probably say my throwing mechanics are terrible,” Skiba said. “And he’ll be right.”