TEMPE, Ariz. — Around 8 a.m. on a Monday, about 16 hours after he had 130 yards and two touchdowns in his second NFL game, Arizona Cardinals rookie wide receiver Marvin Harrison Jr. was back on the practice field catching balls off the Jugs machine.

One by one, the balls hummed off the wheels and shot into Harrison’s hands. About a half-hour later, he had caught about 200.

That Monday wasn’t an anomaly. It doesn’t matter what happened the day, week or, even, month before. To Harrison, who got in the off-day workout with fellow receiver Michael Wilson, it was the first day of a weeklong routine that has become as much a part of Harrison as his 6-foot-4 frame, great hands and Hall of Fame lineage.

The stories of Harrison’s work ethic became the stuff of lore long before his name was called as the No. 4 pick in April’s NFL draft. Nothing has changed since he joined the Cardinals. Harrison catches about 200 balls before practice Monday, Tuesday and Saturday and after practice on Wednesdays, Thursdays and Fridays.

That’s in addition to the hours of work he puts in on his body — recovering, lifting and getting treatment — the playbook and his craft. Committing to the process and being consistent by putting in the work that got him to the NFL has produced 28 catches for 445 yards and five touchdowns through nine games.

But Harrison’s rookie season has been a roller coaster. He followed one catch on three targets in his NFL debut with 130 yards and two touchdowns — all in the first quarter — in Week 2. However, he didn’t have more than 64 yards in a game again until Week 8 against the Miami Dolphins, when he finished with 111 yards and a touchdown.

“I just want to be successful,” Harrison told ESPN. “I want to be great so bad. I want to help my team so bad, and I’m just always going to put my best foot forward for the team, and I think that’s really just where it comes from: just go out there, have fun.”

IN MAY, AROUND the time Harrison started attending rookie practices at the Cardinals’ facility, a member of the team’s nutrition department walked up to left tackle Paris Johnson Jr., Harrison’s former Ohio State teammate, with a message.

“Hey, your boy Marv,” Johnson was told, “he already beat you.”

Johnson had been at the facility daily, showing up 90 minutes before meetings every day. But Harrison didn’t just beat Johnson to the facility. He got there early enough to catch 200 balls and eat breakfast — before Johnson even parked his car.

“To do that as a rookie is very commendable,” Johnson said.

Johnson has seen this all before. Ask any of Harrison’s teammates from his three seasons at Ohio State, where the receiver had 155 catches for 2,613 yards and 31 TDs.

Miami Dolphins offensive lineman Matthew Jones, who was at Ohio State from 2018 to 2023, remembers days when Harrison was on the Jugs machine in the Buckeyes’ indoor facility at 5:15 before 6 a.m. meetings.

“Him and that Jugs machine is like best friends,” Jones said.

Mondays were the least rigorous days for Harrison in college, Buffalo Bills receiver Xavier Johnson said. The work started Tuesday and lasted until Friday. Harrison would be on the field by 7 a.m., catching between 200 and 300 balls before meetings, treatment, class and practice.

After practice, Harrison would go upstairs to eat and get in the cold tub before returning to Ohio State’s indoor facility, Xavier Johnson said. He’d catch another 300 balls until 10 p.m., bringing his total to around 600-700 catches most days.

Harrison’s routine and work ethic was known around the Woody Hayes Athletic Center. By the end of the 2022 season, Denver Broncos defensive back and former teammate Tanner McAllister remembered there being seven other receivers joining the pass-catching sessions.

Atlanta Falcons defensive end Zach Harrison, who played at Ohio State with Harrison in 2021 and 2022, recalled one night he and some teammates went back to the Buckeyes’ facility around 9:30 to work on recovery. They were in the hot tub when they heard the sound of the Jugs machine. When they opened the door to the field, there was Harrison, headphones on, catching ball after ball.

“That dude’s finna be a monster,” Zach Harrison said.

And that’s how it’s always been with Harrison.

“Marv’s been a grinder since we’ve been in high school,” said Philadelphia Eagles linebacker Jeremiah Trotter Jr., who played with Harrison at St. Joseph’s Prep in Philadelphia, where Harrison caught 144 career passes, setting Philadelphia Catholic League records with 2,625 yards and 37 touchdowns. “All the stories that came out in college about him being after practice, working late at night on the Jugs machine, catching balls, he was the same way in college and same way in high school.”

Harrison had a Jugs machine at home in high school, said St. Joseph’s school teammate Malik Cooper, and would roll it outside and catch between 100 and 200 balls a day.

It wasn’t rare for Harrison, Cooper and other teammates to spend weekends playing video games at Harrison’s, and then get on the machine for marathon catching sessions. They’d each catch 100 balls at a time and rotate, with Harrison going first, until sunset. Sometimes they’d fit in a workout in Harrison’s basement or play basketball.

After his football games, Harrison would watch the film with his dad, Hall of Fame receiver Marvin Harrison Sr., breaking down his performance and learning the nuances of the game.

Cooper, who was Harrison Jr.’s quarterback for a season, remembered him staying home instead of going out with his friends some weekends to get in extra work — a preview of how he operated in college.

“He was just always finding ways to get better and not just taking mental reps, [finding] ways during practice that he could harness some physical skills, too,” said Ryne Morrison, Harrison’s receivers coach in high school.

He “turned the corner” his junior year, Morrison said, figuring out how to manage his time better, approach each day and get extra work in. Then Harrison became a pace-setter for his teammates, Morrison said.

“I’m pretty sure that there’s nobody in the state that could guard Marv at all,” Cooper said.

FROM THE DAY Harrison arrived in Arizona, he has approached his job with intensity.

“Just immediately took this job like it’s the most important thing in his life,” fellow Cardinals wide receiver Andre Baccellia said. “Film room, on his iPad all the time, in the meeting room, just seeing he’s always tapped into the plan on his iPad, looking at stuff, watching tape.

“I’m five years in, so I’ve seen rookies come in, and just the level of seriousness and attention to detail that he’s on, it’s next level.”

Wide receivers coach Drew Terrell noticed Harrison’s professionalism during the pre-draft process, and that professionalism carried over through OTAs into the regular season. It hasn’t wavered.

While it might take some players years to come up with a routine, Harrison came into this season ready with his, Terrell said. Former Cardinals receiver and free agent Chris Moore, who’s in his ninth season, said that is “very rare.”

Many NFL receivers catch 25 or 30 passes per day. Harrison’s teammates haven’t heard of anyone catching hundreds of extra passes per day. When receiver Greg Dortch thinks about it, he worries about wear and tear.

“He probably should ice up after because his hands are going to be sore,” Dortch said.

Harrison doesn’t have a hand-care routine, he said, just tape to prepare a pair of calloused hands that have caught thousands of balls. It has led to a number of jammed fingers and surgery on his right thumb, Harrison told ESPN.

However, there are areas of his routine that aren’t as regimented as others.

Harrison doesn’t follow a strict diet, have a personal chef or bring his meals from home. Coach Jonathan Gannon recently asked Harrison what he ate, and the receiver responded honestly: Five Guys.

However, Harrison has figured out a recovery routine that works for him. He’s not a fan of the cold tub but will sit in the hot tub. He opts for massage guns over actual massages and uses air-compression leg sleeves that give him a “restorative massage” to help relieve pain and refresh his legs quicker after games and practices.

“Just watching him work is honestly an honor, to be here and watch him see how he does it just because it is different,” Moore said. “To be out there, to already have these values instilled in him as a rookie and stuff, and nobody has to tell him what to do, he’s just out there doing his job. … It’s truly crazy.'”

IN THE HUSTLE and bustle of a post-practice locker room, Harrison’s chair was empty. While the other Cardinals took off their pads and changed out of their practice gear, Harrison was on the field catching balls off the Jugs machine.

“It’s just who he is,” quarterback Kyler Murray said. “It’s not a surprise. That’s normal.”

Harrison bought a tennis ball machine for his home in Arizona to get more catches in. He was also introduced to playing catch with a rugby ball before practice as a way to open his hands before it’s time to start catching footballs, which are smaller. At Ohio State, Harrison used a basketball.

“The stories are all carrying over,” Terrell said. “He’s always thinking about ways to improve.”

Paris Johnson said Harrison’s life is football.

“Marvin’s very low-key,” Johnson said. “He doesn’t need to be out everywhere with all the action. So his action is what he preps, but when it comes to being around socially, he’s around the guys. He doesn’t need to be out with just anybody, that’s not his entertainment, what entertains him is being around his close friends, his girl, his family, the facility.”

Between the time Harrison was drafted and started practicing two weeks later, he and Gannon had a conversation about Harrison’s renowned work ethic. Gannon knew Harrison put in the work and wanted to make sure his top pick was careful about it.

“If we spaced out how many reps and the amount of workload he gets, and then he goes and runs 100 routes on the weekend, he might be dragging today,” Gannon said during the summer. “Now, he doesn’t drag, but I’m just talking about, I love extra work, but you’ve got to be smart about it. You’ve got to have a routine about what you’re doing.”

What changed the most for Harrison going from Ohio State to the NFL is the structure of his days. His time is more regimented because he has meetings, practice and treatment. He had to forgo some of his early-morning Jugs sessions in favor of his other responsibilities.

Seven weeks into the season, Harrison has found a routine of which Gannon approves. Gannon wanted that kind of consistency, so Harrison would have a baseline if some part of his weekly approach wasn’t working.

“He’s starting to figure that out a little bit,” Gannon said in September. “And it takes time.”

Last week, Gannon said he expected Harrison to have a learning curve, but Harrison has been “1,000 percent” coachable and responsive to the slight adjustments that coaches have been making to his game.

They’ve had to address his stride length, which is longer than the other receivers and sometimes causes Harrison to find himself deeper in his routes than expected in the Cardinals’ rhythm-and-timing based offense. They’ve also worked with Harrison on getting his eyes to where Murray wants them.

“He acts like a 10-year vet,” Gannon said. “And I love where it comes from. It comes from a place of him wanting to help the team first, and then, secondly, is ‘I want to improve my game.'”

Even before the season started, Harrison was putting “a ton of pressure” on himself, Terrell said.

During one early training camp practice, Harrison started talking Terrell’s ear off before a walkthrough, asking him question after question.

“Like, ‘Hey, did you see this route on tape? What’d you think? But did you see this? Should I have done this with my release on tape?'” Terrell remembered. “And, it’s like, ‘Dude, like, calm down. Calm down. Yes, I’ve seen it all. Here’s how we’re going to correct it.’

“But he wants to be perfect.”

Marc Raimondi, Jeff Legwold, Daniel Oyefusi, Marcel Louis-Jacques, Alaina Getzenberg, Paul Gutierrez and Tim McManus contributed to this story.