JACKSONVILLE, Fla. -- The Jacksonville Jaguars drafted running back Leonard Fournette fourth overall last year with plans to build the offense around his physical, smashmouth running style.

Now it's more than fair to wonder if he'll be able to finish his four-year rookie contract with the team.

There are legitimate questions about Fournette's maturity, commitment to football, conditioning, behavior and production. He's been suspended and fined, and some inside the organization wonder if he's willing to put in the work required to be the kind of impact player they envisioned he would become.

And, more important, how much longer are the Jaguars able or willing to wait to find out?

"Must have been meant to happen for some of us to just open up our eyes." Leonard Fournette on the Jaguars' disappointing season

The Jaguars have to hope that 2018 was an eye-opener for Fournette, and he seemed to indicate that it had been in his response to a recent question about how he and his teammates have been able to cope with the immensely disappointing season, when he said they are using it as a learning opportunity.

"It's hard," he said. "[There are] days when you think about a lot of that stuff [and] try not to let it affect you. The talent we had on this team, how our season went down ... got to grow out of it.

"Must have been meant to happen for some of us to just open up our eyes."

The Jaguars (5-10) certainly hope Fournette has gotten that message, because there's a long list of concerns about just how much they can rely on him -- or if he should even be part of the team's future plans, regardless of which coach and executives are in charge.

One season after missing two games with injuries, Fournette missed six full games and half of two others in the first eight weeks of 2018 with a right hamstring injury, and there was mounting frustration inside the organization about the length of his absence. Jacksonville built its offense around a power run game, and the unit had a hard time functioning consistently without Fournette on the field.

All that time away apparently affected his conditioning. He looks heavier than when he reported for training camp, when he said he was down to 223 pounds (his lowest weight since his sophomore season at LSU). The CBS broadcast crew during Sunday's game against Miami said Fournette, who reported at 240 pounds as a rookie in 2017, told them he was 233 pounds.

That came a week after he got the corner against the Washington Redskins but was unable to accelerate and run away from the defense the way he did as a rookie during 90- and 75-yard touchdown runs. Fournette recorded the highest speed of any ball carrier in the NFL in 2017 when he hit 22.05 mph on his 90-yard run against the Steelers, per NFL Next Gen Stats.

It's unusual for an NFL player to gain weight during the season, and Fournette was unable to do much, if any, conditioning during the time he was rehabbing his hamstring. Even so, it has been seven weeks since he returned to the lineup.

Fournette missed another game this season as punishment for leaving the bench and fighting with Bills defensive lineman Shaq Lawson during the Jaguars' 24-21 loss at Buffalo on Nov. 25. Fournette said he ran across the field because he saw Lawson shove Carlos Hyde and wanted to defend his teammate.

The NFL suspended him the following game without pay. It's the second time he's missed a game because of disciplinary reasons. The team made him inactive as a rookie as punishment for leaving Jacksonville early and missing a team photo during the bye week.

Fournette also was caught on video yelling at a fan in the stands during the team's embarrassing loss at Tennessee on Dec. 6. The video clip released on TMZ.com shows Fournette yelling that he was going to "beat your ass" to an unknown fan before two people escort the running back away.

Fournette hasn't produced when he's been in the lineup, though the fact that the offensive line has been decimated by injuries is a significant reason for that (four of the five starters are on injured reserve, and two of the current starters weren't on the team until October). He has rushed for 439 yards and five touchdowns and is averaging just 3.3 yards per carry; as a rookie he rushed for 1,040 yards and nine touchdowns on 268 carries (3.9 average).

The Jaguars have put him on the bench because of his lack of production. He didn't have a carry in the third quarter in Week 15 against Washington, and he had one carry in the fourth quarter and left the game after hurting his foot; rookie David Williams -- who was playing in just his fourth game -- carried the ball.

Fournette wasn't on the field when the Jaguars were trying to run out the clock against Miami late in Sunday's fourth quarter, either. Those carries went to Hyde, who had five carries for 37 yards on the Jaguars' final possession. Fournette, who ran for 7 yards on the first play of the drive before leaving the game, finished with 43 yards on 18 carries (2.4 per carry).

"A lot of times it's who is running well at that point," coach Doug Marrone said. "With Williams, it was a different situation where we were trying to get him carries in a game where we were behind. I wanted to make sure I got him carries, and he did well. This week Carlos [Hyde] was running well and we stuck with Carlos and he was able to finish out the game.

"I wouldn't look too much into all that stuff. We're talking about split-second decisions."

Still, it's not a good look that the player Jacksonville drafted in part to chew up yards and clock wasn't on the field.

Fournette hasn't criticized the team's decisions publicly and is well-liked by his teammates, which is why he was voted one of the offensive captains at the beginning of the season. But it's clear he has a lot of work to do in regard to learning how to be a professional football player. That's why it's no coincidence that his locker is next to Calais Campbell's. The Jaguars hoped the veteran defensive end would be a positive influence.

It's not an easy adjustment from college to the NFL, and some players make the transition more quickly than others.

"I think the biggest thing is you have to learn that now there's a process when you get paid to show up, instead of being the college kid when you're playing for the love of the game and hopefully one day to make it to the NFL," Campbell said when asked about what it takes to become a good pro. "But when you're here, when you're actually a paid employee, you have to understand responsibility comes with that. Most of these guys, like around the league, most rookies it takes a while to learn. It's a growing process. You have to mature. That's why very rarely can you depend on a rookie consistently. Now, it has happened a lot lately. Some of these rookies come in better prepared than normal, but usually it takes time for rookies to adjust.

"I had a lot of good examples when I was a rookie, but I try to be what they were to me to any rookie. When rookies are coming in I try to let them know that, 'Hey, I'm a resource. Use me as much as you want to. I've got a lot of knowledge. I'd love to pass it down.' A lot of times rookies get tired of hearing me, because they try to get too much knowledge, but at the end of the day experience is the best way to learn, so you have to go through it and just kind of learn as you go."

That's what Fournette is trying to do now, but the process needs to be sped up because there is no player on the roster with more to prove in 2019 than Fournette. On and off the field.